Millions of people living in South Asia face a deadly threat from heat and humidity driven by global warming according to a new study.

Most of India, Pakistan and Bangladesh will experience temperatures close to the limits of survivability by 2100, without emissions reductions.
The research says the fraction of the population exposed to dangerous, humid heat waves may reach 30%.
South Asia is home to one-fifth of the world's inhabitants.
Most official weather stations around the world measure temperature with two thermometers.
The first, or "dry bulb" instrument, records the temperature of the air. The other, or "wet bulb" thermometer, measures relative humidity in the air and the results are normally lower than just the pure air temperature.
For humans, this wet bulb reading is critically important.
While the normal temperature inside our bodies is 37C, our skin is usually at 35C. This temperature difference allows us to dissipate our own metabolic heat by sweating.
However, if wet bulb temperatures in our environment are at 35C or greater, our ability to lose heat declines rapidly and even the fittest of people would die in around six hours.
While a wet bulb 35C is considered the upper limit of human survivability, even a humid temperature of 31C is considered an extremely dangerous level for most people.
Recorded wet bulb temperatures on Earth have rarely exceeded 31C. However, in 2015 in Iran, meteorologists saw wet bulb temperatures very close to 35C.  In the same summer, a deadly heat wave killed 3,500 people in India and Pakistan.
This understanding of the potentially deadly impact on humans of wet bulb temperatures is key to this new study.
The researchers involved came to their conclusions by using a high resolution climate model, that was tested against observations.
They projected wet bulb temperatures to the end of this century using two different climate change scenarios.
When the model examined a high emissions future, the wet bulb temperature would approach the 35C threshold "over most of South Asia, including the Ganges river valley, north eastern India, Bangladesh, the eastern coast of China, northern Sri Lanka and the Indus valley of Pakistan".
According to the scientists, around 30% of the population is projected to live in a climate characterised by a median of the maximum annual wet bulb temperature of 31C or more. At present, the number of people facing this level of threat is essentially zero.
"The valleys of the Indus and the Ganges rivers are where the water is, they're where the agriculture is and they're where the population has exploded," author Prof Elfatih Eltahir from the Massachusetts Institute of Technology (MIT) told BBC News.
"Our map that shows where the temperature extremes are, it's the same place that you have relatively poor people who predominantly have to work in agriculture and there are so many that they happen to coincide in a region where the hazard is maximised."
If the rise in global temperatures is contained to just over two degrees, roughly in line with the Paris Climate Agreement, the fraction of the population exposed to humid heat above 31C drops to 2%.
Heat waves up to and beyond 31C are projected to become much more frequent if little action is taken on cutting carbon. In most locations, the once-every-25-year heat wave in the present climate is projected to become an approximately once-a-year occurrence. If the limitations agreed in Paris are met, these heat waves are likely to happen every two years.
"Climate change doesn't look like an abstract concept if you look at India," said Prof Eltahir.
"This is something that is going to impact your most vulnerable population in ways that are potentially pretty lethal. But it is avoidable, it is preventable."
Other researchers say the "damaging and downright deadly" conditions described in this study are likely to occur if the world doesn't embrace rapid and substantial cuts in carbon emissions.
"This study provides a crucial glimpse of the future," said Prof Matthew Huber from Purdue University, US, who wasn't part of the research team.
"Either we - the whole world - decide to reduce carbon emissions substantially or we face a highly dangerous scenario in one of the most populous regions in the world, with a deep history and culture, and also a history of political instability."
According to Prof Christoph Schaer from the Institute of Atmospheric and Climate Science at ETH Zurich, the work is "alarming".
"The study is credible as extremely hot and humid heat waves already occur under current climatic conditions in some of the areas considered," he said.
"As conditions are close to a critical health threshold already today, a warming of a few degrees could strongly increase the risk of deadly heat waves."
The study has been published in the journal Science Advances.
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Southampton boss Ronald Koeman fears Victor Wanyama could be out for up to five weeks after the midfielder suffered a hamstring injury in Wednesday's FA Cup win at Ipswich.

Wanyama had to be taken off seconds before half-time in the third-round replay, which the Saints won 1-0.
Koeman, who said playing replays in an already busy schedule is "crazy", had initially planned to only play Wanyama for 45 minutes.
"It is a real negative," he said.
"We already have some other injuries. If it is a hamstring injury then he will be out for four to five weeks."
Wanyama has been a key player for Southampton this season, making 24 appearances in all competitions.
Injury means he could miss the visit of Liverpool on 22 February, as well as games against Newcastle, Swansea, Queens Park Rangers and West Ham.
When asked if he will sign cover for Wanyama, Koeman added: "I won't necessarily go into the transfer market, I have young lads who we can use."
Southampton, who are fighting for a top-four finish in the Premier League, already have a number of injury concerns, with midfielder Morgan Schneiderlin having to miss Wednesday's game against Ipswich because of a leg injury.
Media playback is not supported on this device
"Schneiderlin has a similar thing to when he came back from the France national team - an abductor problem in his right leg," added Koeman.
"He will be out for three to four weeks, like Toby Alderweireld. But we have a lot of young players.
"We have good young lads and a good under-21 side. But sometimes it's too much and we have to protect them. We will see what we need to do.
"We don't train in the last few weeks because we play so much and it's a problem about the schedule for players during the winter break. In what is normally a winter break, we have to play.
"We have another replay. Why replays? It's another game and it's crazy."


Hampshire have signed Ireland seamer Craig Young on a short-term loan deal.

The 26-year-old right-arm bowler has played nine one-day and 10 Twenty20 internationals for Ireland, and was previously on the books at Sussex.
He will appear for Hampshire's second XI against Somerset on Monday.
Hampshire are currently suffering an injury crisis in their bowling department, with Fidel Edwards, Reece Topley, Gareth Berg and Ryan Stevenson all unavailable.


A US court has ruled that President Obama's plans to protect almost five million illegal immigrants from deportation must stay on hold.

The Justice Department wanted an appeals court to overturn a block imposed after 26 states launched a legal challenge to the action.
But the court denied the government's request.
The states say the action is unconstitutional, but the White House says Mr Obama acted within his powers.


A large number of works of art have been seized from a Cotswold art gallery after allegations of fraud and theft.

Gloucestershire Police said they had received allegations that Opus Fine Art in Stow-on-the-Wold had been "dishonestly retaining or selling" art.
The gallery deals in works by high profile artists including Damien Hirst.
A police spokesman said investigations were ongoing to establish ownership of the seized property.
The Independent newspaper reported the owners, Donald Smith and Emma Poole, were believed to have moved to the south of France.


League Two side Mansfield Town have signed Peterborough United forward Shaquile Coulthirst on loan until the end of the season.

The Stags have an option of signing a permanent deal with the 22-year-old striker.
Coulthirst, a graduate of Tottenham's academy, made just one first-team appearance while at White Hart Lane.
The striker also had loan spells with Leyton Orient, Torquay, Southend, York and Wigan.
Coulthirst will join his former team-mate Hayden White at Field Mill, after he was signed on loan from Posh a week ago.
Find all the latest football transfers on our dedicated page or visit our Premier League tracker here.


Substitute Abdallah El Said scored a late winner for Egypt to knock Uganda out of the Africa Cup of Nations.

After a drab game with few chances for either side, Mohamed Salah teed up El Said, who struck firmly past Uganda keeper Denis Onyango on 89 minutes.
Uganda's Joseph Ochaya earlier had a goal correctly disallowed for offside.
The win means Egypt play Ghana on Wednesday with top spot of Group D still at stake, while Uganda are out of their first tournament since 1978.
Ghana secured their place in the quarter-finals with a 1-0 victory over Mali earlier on Saturday.
On a deteriorating pitch in Port-Gentil, seven-times champions Egypt failed to break down a resolute Cranes defence for long periods.
Onyango made an impressive clearing header to deny the onrushing Salah at the end of an otherwise lifeless first half.
Uganda began the second half brightly, forcing veteran Egypt goalkeeper Essam El Hadary to punch several set-pieces clear but ultimately failed to register a shot on target as Ochaya turned in Faruku Miya's through ball from a clearly offside position on 52 minutes.
El Said blasted a shot well over when unmarked and Marwan Mohsen went close for the Pharaohs with a header, but Egypt appeared to be heading for their second consecutive goalless draw.
However, an otherwise quiet Salah showed great composure late on to check his shot and play in El Said with a reverse pass, the substitute's close-range shot evading Onyango.
Uganda now face Mali in the final round of group games on Wednesday, with Mali needing a win and for Ghana to beat Egypt by two goals or more if they are to qualify.
Match ends, Egypt 1, Uganda 0.
Second Half ends, Egypt 1, Uganda 0.
Offside, Uganda. Murshid Jjuko tries a through ball, but Muhammad Shaban is caught offside.
Hand ball by Moses Oloya (Uganda).
Kahraba (Egypt) wins a free kick in the attacking half.
Foul by Hassan Wasswa (Uganda).
Offside, Egypt. Kahraba tries a through ball, but Marwan Mohsen is caught offside.
Substitution, Uganda. Moses Oloya replaces Denis Iguma.
Mohamed Shafy (Egypt) wins a free kick in the defensive half.
Foul by Khalid Aucho (Uganda).
Goal!  Egypt 1, Uganda 0. Abdallah El Said (Egypt) right footed shot from the centre of the box to the centre of the goal. Assisted by Mohamed Salah.
Attempt missed. Amr Warda (Egypt) right footed shot from outside the box is too high. Assisted by Mohamed Shafy.
Corner,  Uganda. Conceded by Ahmed Fathy.
Attempt blocked. Joseph Ochaya (Uganda) left footed shot from outside the box is blocked. Assisted by Nicholas Wadada.
Delay over. They are ready to continue.
Substitution, Uganda. Nicholas Wadada replaces Faruku Miya.
Substitution, Egypt. Kahraba replaces Trezeguet.
Delay in match Khalid Aucho (Uganda) because of an injury.
Attempt saved. Marwan Mohsen (Egypt) left footed shot from outside the box is saved in the centre of the goal. Assisted by Amr Warda.
Tonny Mawejje (Uganda) wins a free kick in the defensive half.
Foul by Mohamed Elneny (Egypt).
Delay over. They are ready to continue.
Delay in match Mohamed Shafy (Egypt) because of an injury.
Foul by Muhammad Shaban (Uganda).
Ali Gabr (Egypt) wins a free kick in the defensive half.
Hand ball by Trezeguet (Egypt).
Attempt missed. Marwan Mohsen (Egypt) header from the centre of the box is just a bit too high. Assisted by Mohamed Shafy with a cross following a set piece situation.
Foul by Murshid Jjuko (Uganda).
Marwan Mohsen (Egypt) wins a free kick in the attacking half.
Godfrey Walusimbi (Uganda) wins a free kick on the left wing.
Foul by Ahmed Fathy (Egypt).
Attempt saved. Trezeguet (Egypt) right footed shot from the centre of the box is saved in the centre of the goal.
Attempt blocked. Trezeguet (Egypt) right footed shot from outside the box is blocked. Assisted by Amr Warda.
Substitution, Egypt. Amr Warda replaces Ramadan Sobhi.
Substitution, Uganda. Muhammad Shaban replaces Geofrey Massa.
Attempt missed. Abdallah El Said (Egypt) right footed shot from the centre of the box is high and wide to the right.
Foul by Joseph Ochaya (Uganda).
Ahmed Fathy (Egypt) wins a free kick in the defensive half.
Substitution, Egypt. Abdallah El Said replaces Tarek Hamed.
Foul by Geofrey Massa (Uganda).


US oil giant Chevron says it will appeal against an $8.6bn (Â£5.3bn) fine imposed by Ecuador judges, carrying on a long-running row over pollution.

Chevron's Kent Robertson told the BBC the case was an "extortion scheme", and accused Ecuador's state-run firm of polluting the country's Amazon region.
The legal wrangle has been going on for almost two decades, and has spawned lawsuits in the US and Ecuador.
Analysts say further appeals are likely to drag on for years.
The oil firm Texaco, which merged with Chevron in 2001, is accused of dumping billions of gallons of toxic waste into unlined pits and Amazon rivers between 1972 and 1992.
Campaigners say crops were damaged and farm animals killed, and that local cancer rates increased.
But Chevron says Texaco spent $40m cleaning up the area during the 1990s, and signed an agreement with Ecuador in 1998 absolving it of any further responsibility.
Mr Robertson, the firm's spokesman, told the BBC's World Today programme that Texaco had "operated admirably" and blamed Ecuador's state-run firm Petroecuador for any ongoing problems.
"The oilfields in question have been solely operated by the government of Ecuador's own oil company Petroecuador for the last 20 years," he said.
"Petroecuador has a deplorable environmental record and Chevron is getting blamed for actions in a country that we've never even operated in."
He accused Petroecuador and Ecuador's government of failing to live up to their responsibilities. Neither have responded to the claims.
The lawsuit was brought on behalf of 30,000 Ecuadoreans, and their lawyer Pablo Fajardo described the court ruling as "a triumph of justice over Chevron's crime and economic power".
But he said the damages were not enough, and pledged to appeal.
Environmentalists hoped the case would set a precedent, forcing companies operating in developing countries to comply with the same anti-pollution standards as in the industrialised world.
US-based lobby groups Amazon Watch and Rainforest Action Network said in a joint statement that the decision was "historic and unprecedented".
"Chevron has spent the last 18 years waging unprecedented public relations  and lobbying campaigns to avoid cleaning up the environmental and public health  catastrophe it left in the Amazon rainforest," the groups said.
But analysts say Chevron is determined that it will not pay the fine.
Earlier this month, the firm took its case to the Permanent Court of Arbitration in The Hague, which ordered Ecuador to suspend enforcement of any judgement against Chevron to allow arbitration to continue.
Separately, Chevron has also filed a case in the US courts accusing the claimants and lawyers in the case of racketeering, tampering with witnesses and obstructing justice.


The government wants to increase the amount of money on offer for those affected by the blood contamination scandal by a further £100m, public health minister Jane Ellison has said.

Thousands of people were infected with Hepatitis C and HIV through NHS blood products in the 1970s and 80s.
Ms Ellison said the money would come from the Department of Health's budget, and she apologised again to victims.
In March last year the Penrose report was published after a six-year inquiry.
Lord Penrose, a retired judge, concluded that more should have been done to screen blood and donors for hepatitis C in the early 1990s.
Many of those affected were in Scotland, which was the only part of the UK to hold an inquiry.
Ms Ellison said the government was now opening a 12-week consultation on the new payment proposals.
She said the £100m is in addition to the £25m which was announced in March - taking the total to £225m over the five years to 2020.
"This is significantly more than any previous government has been able to provide for those affected by this tragedy," she told MPs in the Commons.
But she also admitted that "no amount of money could make up for the impact" blood infections had on victims and families.
The contaminated blood scandal has been described as the worst treatment disaster in the history of the NHS, and was responsible for the deaths of hundreds of people - many of whom were haemophilia patients.
In Scotland the Penrose report said that 478 people acquired the Hepatitis C virus from blood product therapy, and 2,500 acquired the virus from blood transfusion in Scotland between 1970 and 1991.
Sixty patients acquired HIV from therapy with blood products, and 18 from blood transfusion in Scotland.
The scandal happened before the creation of the devolved Scottish Parliament, which now has full responsibility for the NHS in Scotland.
When the Penrose report was published last year there was an angry response from victims and relatives, some of whom labelled it a "whitewash", and burned copies of the report on the streets of Edinburgh.
Ms Ellison also said that within the consultation there was a proposal for all those currently receiving regular support to have that funding increased to £15,000 a year, and those who are co-infected - as in contaminated with more than one virus - should get £30,000.
She also said the government wanted to "focus on those who are infected" and be able to "respond to new advances in medicine".
As well as the extra cash the government is also proposing to make a single body responsible for a new support scheme with the promise of more help for certain groups of people, such as those with Hepatitis C.
"There is a large population within the infected blood community who currently do not receive any regular financial support. These are the people with Hepatitis C.
"I believe it is important that everybody receives support from the new scheme and that this is linked to the impact that infection has on their health," she said.
Shadow health minister Andrew Gwynne praised the government's intentions for a consultation, but noted the "injustice felt by many victims".


Wanting a cup of tea has been used as an analogy for sexual consent in a YouTube video released as part of a police awareness campaign.

Thames Valley Police's "consent is everything" campaign aims to educate people about the need to get consent, rather than assume it has been given.
It shows how "ludicrous" it would be to force someone to drink tea if they had turned it down or changed their mind.
And it tells the viewer not to pour tea down the throat of someone unconscious.
Thames Valley Police said awareness of what sexual consent meant was "vital".
"The law is very clear. Sex without consent is rape," said Det Ch Insp Justin Fletcher.
The video was originally created by Blue Seat Studios and blogger rockstardinosaurpirateprincess, who wrote the text on which the script is based earlier this year.
Towards the end of the near-three minute video, viewers are asked: "If you can understand how completely ludicrous it is to force people to have tea when they don't want tea, and you are able to understand when people don't want tea, then how hard is it to understand when it comes to sex?"
Other lines in the video include: "If they say 'no thank you', then don't make them tea at all. Just don't make them tea. Don't make them drink tea, don't get annoyed at them for not wanting tea. They just don't want tea, OK?"
And the voiceover warns: "If they are unconscious, don't make them tea. Unconscious people don't want tea and they can't answer the question 'do you want tea?' because they are unconscious."
The campaign has been launched by police alongside the Thames Valley Sexual Violence Prevention Group.
Christina Diamandopoulos, co-director of Rape Crisis in Wycombe, Chiltern and South Buckinghamshire, said: "For too long there have been myths around the subject of consent, particularly that it is a 'grey' area.
"In reality it has never been a 'grey' area, and this campaign, which we are proud to be part of, makes that clear."


Rhondda MP Chris Bryant has become the latest Labour shadow cabinet member to resign in protest at Jeremy Corbyn's leadership over the EU referendum.

The former shadow Commons leader tweeted: "We need someone new to unite and lead Labour."
In his resignation letter he told Mr Corbyn: "If you refuse to step aside I fear you will go down in history as the man who broke the Labour Party."
But Mr Corbyn said he will not "betray the trust of those who voted for me".
In the letter, which was also published on Twitter, Mr Bryant wrote that Mr Corbyn's "inability to give a clear, unambiguous message to Labour voters" had "significantly contributed to the result" of the EU referendum.
Mr Bryant wrote: "Sadly, the referendum has shown that you and your team cannot run an effective national campaign and that you do not command the support of the country."
He said: "I urge you, because you are a decent man to do the decent thing and take the only action that can avert potential disaster by stepping aside.
"If you do so I believe future generations will praise your selflessness."
Mr Bryant was the latest of a string of shadow cabinet members who resigned in protest at Mr Corbyn's leadership.
In a statement Mr Corbyn said: "I regret there have been resignations today from my shadow cabinet. But I am not going to betray the trust of those who voted for me - or the millions of supporters across the country who need Labour to represent them."
He added: "Those who want to change Labour's leadership will have to stand in a democratic election, in which I will be a candidate."
Earlier Aberavon Labour MP Stephen Kinnock warned his party will suffer heavy losses if Mr Corbyn leads it into a general election this year.
Mr Kinnock, asked on BBC Sunday Politics Wales if he feared that many MPs could lose their seats, said: "That is absolutely central to our concerns.
"I do not see him as a negotiator with the skills and experience that we need to take us forward at this unprecedented time.
"I accept that the membership gave Jeremy a huge mandate, but that was then and this is now. Everything has changed."
Mr Kinnock added: "We have to ensure that we go into that general election with a leader who is right in the context of a post-Brexit referendum United Kingdom."
But Darren Williams, secretary of the left-leaning Welsh Labour Grassroots movement, told BBC Radio Wales it was "disappointing that Labour isn't uniting around Jeremy Corbyn".
Wrexham MP Ian Lucas said he wrote to Mr Corbyn urging him to stand down after his local constituency party passed a motion of no confidence in the leader.
He told BBC Radio Wales he was disappointed by the sacking of Hilary Benn as shadow foreign secretary.
"It's symptomatic of the fact unfortunately the present leader is not capable of leading the Labour Party effectively at this time of national crisis," he added.
Former Welsh Secretary Lord Hain said: "It's been very evident for a while that the majority of Labour-inclined voters do not think Jeremy is capable of winning the next election for us.
"That is the reality which cannot be ignored. That's the issue that needs to be confronted by party members who voted for him."
But in a blog post, Newport West Labour MP Paul Flynn accused shadow cabinet members of "playing party games" while jobs were in peril.
He wrote: "It's a disgrace that political parties are playing self-indulgent games with orchestrated resignations on the hour as part of an organised treachery."
Mike Hedges, Labour AM for Swansea East who supported Corbyn's leadership bid, told BBC Wales: "Less than 12 months ago Jeremy Corbyn won the biggest mandate of any Labour leader.
"This referendum had members of the Labour party on different sides.
"I do not understand why some MPs are blaming Jeremy Corbyn for the referendum result. We should be uniting as a party behind the leader to hold the Tory party to account."


The Democratic Unionist Party has been fined £4,000 by the Electoral Commission for an inaccurate spending return.

It relates to spending on the May 2016 Northern Ireland Assembly election.
The return included payments of £49,200 which should not have been attributed to party spend, but as individual candidate expenditure.
The commission accepted that payments were properly reported by candidates and were duplicated in party returns.
The return was also missing two payments to the value of £400 which should have been reported.
The DUP says it has reviewed its procedures to prevent a recurrence of the errors.
The party has paid the fine.


A woman whose five-year-old daughter died from a rare illness has finished a 6,000 mile (9,656km) memorial walk.

Natalia Spencer has walked around the British coastline to deal with the grief of losing her "beautiful daughter" Elizabeth.
She has also raised more than Â£115,000 for Bristol Children's Hospital, where her daughter died.
Ms Spencer completed the walk at Durdle Door, in Dorset, from where she set off in February last year.
She said she was "overwhelmed with emotions" having finished the trip.
Ms Spencer, from Cheltenham, said the beach at Durdle Door was "emotionally significant" because it was the last seaside location she visited with her daughter.
Elizabeth died shortly before Christmas in December 2015 from Hemophagocytic lymphohistiocytosis (HLH) - a condition which sent her immune system into overdrive.
Her mother said she wanted to "give something back" and decided to raise money for the hospital.


Regulators are to begin investigations into senior managers at HBOS, the bank which collapsed during the financial crisis.

Two reports, published in November, criticised the regulator at the time for failing to take action.
One of those reports, by barrister Andrew Green QC, said regulators should consider banning 10 former HBOS executives.
A new investigation has now been announced by regulators.
"The Financial Conduct Authority (FCA) and the Prudential Regulation Authority (PRA) have decided to start investigations into certain former HBOS senior managers," the regulators said.
"These investigations will determine whether or not any prohibition proceedings should be commenced against them. The FCA and PRA continue to review materials with a view to making further decisions regarding other former HBOS senior managers."
No details are being given as to the exact nature of the investigations, who is being investigated, or the timeframe of the inquiry.
A Bank of England/FCA report examined the failure of HBOS, while Mr Green examined decisions taken by the Financial Services Authority, the City regulator at the time of the HBOS demise. Both were published in November.
So far the only person to have been banned is Peter Cummings, who was previously the head of corporate lending at HBOS. In 2012, he was fined Â£500,000, and banned from senior positions in banking.
In his report, Mr Green suggested that the Bank of England's PRA and the FCA should consider prohibition proceedings against former executives.
That included Andy Hornby, HBOS chief executive from 2006 to 2009. Mr Green said the FSA was "misguided" when it took the decision not to take action against Mr Hornby.
Other former HBOS executives named in the report included Lord Stevenson, and Mike Ellis, the former group finance director at HBOS.
Lindsay Mackay, the head of HBOS's Treasury division from 2004, could also be banned, November's report said.
James Crosby, HBOS chief executive from 2001 to 2006, has retired. He gave up his knighthood in 2009, and surrendered part of his pension.
Eight former non-executive directors of HBOS were criticised in the report, although they said they disagreed with its findings.
The eight, including Lord Stevenson and Carphone Warehouse founder Sir Charles Dunstone, said the report had downplayed the "unforeseeable" effects of the financial crisis.


Jayaram Jayalalitha was the undisputed leader of the governing party in the southern Indian state of Tamil Nadu, but her sudden death has raised questions over who will replace her and what direction the party will take.

It will take a while for supporters and other leaders of the All India Anna Dravida Munnetra Kazhagam party, or AIADMK, to come to terms with the huge void created by the death of Jayalalitha, one of India's most flamboyant and controversial leaders.
The party, founded in 1972 by the charismatic MG Ramachandran, known as MGR, a film star turned politician, has been playing a crucial role in providing political stability in Tamil Nadu, which is among the most important Indian states economically and politically.
Jayalalitha's death has triggered an air of uncertainty among the 75 million Tamils who have been used to seeing the AIADMK either as a governing party or as the main opposition for nearly four decades.
Political stability has played a key role in Tamil Nadu's development over the years.  Its economy has been growing at a rate of around 12% in the past 10 years, much higher than the national average of around 8%.
Tamil Nadu is also the second largest economy among Indian states, next only to Maharashtra. Its Gross Domestic Product (GDP) in 2015 was estimated to be around $150bn (Â£119bn). And as a whole, GDP per person in Tamil Nadu is 68% higher than the national average of $1,390 (Â£1,102) a year.
For the moment, one of Jayalalitha's trusted lieutenants, O Panneerselvam, has taken over as chief minister. The smooth transition of power has surprised everyone. But there are challenges ahead.
"The party does not have any other leader who is similarly charismatic or popular. That is a vacuum. Right from its inception, the AIADMK has had popular leadership. For the first time, the party does not have a popular figure," says Gnani, a veteran political analyst.
It is well known that there is no second - or even third - line of leadership in the party. The AIADMK flourished and succeeded mainly because of the charisma of Jayalalitha after she took over the party in 1990. At the helm, she never allowed anyone to challenge her and those who showed signs of rebellion were summarily dismissed.
As a woman leader in a male-dominated society, she stamped her authority to instil respect or even fear among her party's men. Her autocratic style led to her ministers and senior party members prostrating in front of her in public, sometimes even in front of her car, to get her blessing or attention.
The AIADMK leadership - both MGR and Jayalalitha - appealed directly to its supporters, mostly in rural and semi-urban areas. The middle-level leaders were usually hand-picked and most of them had no political base of their own.
The winning formula was achieved by offering free tablets, bicycles, televisions and money, and also by striking alliance with smaller or caste-based political parties. The party's election symbol, Two Leaves, introduced by MGR, is still a powerful tool to attract votes.
There is speculation that Jayalalitha's long-time friend and confidante Sasikala Natarajan is likely to play a crucial role in the party's affairs and establish a power structure around her.
Though she was close to the former leader, Mrs Natarajan was never given any official position by Jayalalitha. Mrs Natarajan and her family members are influential within the party, but they do not have any political base of their own.
If there is any trouble within the party over the growing influence of Mrs Natarajan, that will work to the advantage of the main opposition in Tamil Nadu, the Dravida Munnetra Kazhagam (DMK). It is not uncommon in Tamil Nadu politics to engineer a split in the rival camp to bring down the government.
Some regional leaders of the AIADMK, who were sidelined by Jayalalitha, may use the opportunity to stage a comeback and demand ministerial berths.
Any infighting within the AIADMK is also likely to have an impact at the national level politics. In the past two decades, India's political direction has been dictated by powerful regional parties and the AIADMK was one of them.
It took 30 years for a single party to achieve an outright majority in the Indian parliament, in 2014. Support of the regional parties was crucial in the formation of a national coalition government.
But the political equation changed after Narendra Modi led the BJP to power two years ago.
Whether in a coalition or not, an assertive Jayalalitha never hesitated for a moment to take on the central government, even eclipsing her mentor MGR. She castigated the federal government over their stance on the Sri Lankan Tamil issue or the Cauvery river water sharing dispute with neighbouring Karnataka state.
There are concerns now that a weak AIADMK beset by internal squabbles will reduce the party's influence in central policies affecting the state.
"Regional parties have already lost their influence after the BJP got an absolute majority in parliament. If infighting erupts within the AIADMK, it will diminish the power and political leverage of the AIADMK. But the BJP still needs their support in the Rajya Sabha (Upper House) to pass crucial bills and laws," says AR Venkatachalapathy, historian and professor at the Madras Institute of Development Studies.
If nothing goes wrong, the present AIADMK government is expected to complete its full term and the next state assembly elections are scheduled for 2021.  The challenge for the AIADMK will be how it will face the electorate if there is any election in the interim period.
The two Dravidian parties - AIADMK and DMK - have been ruling the state for nearly five decades. The national parties, like Congress and the BJP, have been waiting for decades to make inroads in Tamil Nadu. Is it the right moment?
"It AIADMK weakens, then the main opposition DMK will benefit. I don't think any national party (like Congress or the BJP) will benefit from the situation. The DMK will move into the space," says N Ram, former editor-in-chief of the Hindu newspaper.
Tamil Nadu has witnessed lots of political drama over the years, but it is now entering a new phase and getting used to a life without Ms Jayalalitha for the first time in 35 years. More twists and turns are on the cards.


The America's Cup sailing competition was ended early, after extreme weather forced the organisers to cancel the second day of racing.

The Duke and Duchess of Cambridge were among the crowd who had turned up to see the race in Portsmouth yesterday.
They were hoping to cheer on Olympic champion Sir Ben Ainslie as he tried to become the first British challenger to win the trophy.
But the race was abandoned after winds reached more than 30mph.
The America's Cup is the most famous sailing event in the world.
It was named after a boat called America, which beat the best Britain could offer in a race around the Isle of Wight in 1851.
It is one of the most difficult sporting trophies to win, with the best sailors racing in the fastest boats against each other. It's a race of speed, strategy and tactics.
"It was the right call because in those conditions the boats would have capsized and people would have got hurt," said Ainslie.
"You can't mess around with these boats, they are very powerful and if they get out of control there is carnage.
"But we were delighted with the results and delighted to perform well in front of a home crowd. The event has been a huge success and it shows what support there would be if we were hosting the America's Cup here."
Ainslie's boat was first and second in the two races that took place on Saturday, meaning that he still won overall.


An investigation has been launched by police in the Isle of Man after a man was found dead at a property in Douglas.

The body of 35-year-old Christopher Lennox was found by police after they were called to an address on Tynwald Street on Sunday afternoon.
A police said the cause of death is being treated as "unexplained" with the cause "yet to be established."
Det Sgt Bobby Syme said the Coroner of Inquests has been notified.


France's highest administrative court is being asked to overturn beach bans imposed by 26 towns on women in full-body swimsuits known as "burkinis".

A human rights group and an anti-Islamophobia association argue the bans are in breach of French law.
Mayors, particularly on the Riviera, say the bans are protecting public order and rules on secularism.
Opinion polls suggest most French people back the bans but Muslims warn they are being targeted unfairly.
According to an Ifop survey, 64% of French people are in favour of the bans while another 30% are indifferent.
The bans appeared to have split senior members of the French government.
Prime Minister Manuel Valls waded into the debate on Thursday, backing the mayors who had made public order decisions in the aftermath of the jihadist attack on Nice last month. The burkini represented the "enslavement of women", he added.
Education Minister Najat Vallaud-Belkacem said that while she disapproved of the burkini as a feminist, she saw the bans as unwelcome and objected to the idea that the clothing a woman wore on a beach could have any link to terrorism or jihadist group Islamic State.
The controversy has intensified in France after pictures of police appearing to enforce the ban prompted widespread anger. Some of the women pictured in Nice and Cannes were not wearing burkinis.
Siam, 34, a mother from Toulouse, was fined €11 (£9; $12), although she insists she was not wearing a burkini at the time but leggings, a jacket and a headscarf.
"The policeman told me I had to wear correct clothing and wear the hijab as a headband. But I left the beach and kept my hijab on," she told the BBC World Service. "I felt like a stranger in my own country. Some people came to comfort me but others insulted me."
French daily Liberation said on Thursday that the local laws were "stupid" and a gift to Islamist propaganda.
Anouar Kbibech, president of the French Council of the Muslim Faith (CFCM), said he was "concerned over the direction the public debate is taking", citing the "growing fear of stigmatisation of Muslims in France".
Most of the beaches where bans have been imposed are on the Riviera in south-east France.
However, few are thought to have issued fines other than the authorities at Cannes and Nice, where more than 20 fines have been handed out.
France's Human Rights League (LDH) and the anti-Islamophobia association (CCIF) argue the bans contravene freedom of opinion, religion, clothing and movement.
They failed to persuade a court in Nice this week to overturn a ban at Villeneuve-Loubet west of Nice and have taken their case to France's highest administrative court, the Council of State (Conseil d'Etat). A ruling is expected on Friday afternoon.
In London, about 50 people gathered outside the French embassy to protest against the burkini ban.
After a militant Islamist ploughed a lorry into families on the seafront at Nice on 14 July, killing 86 people, the city's authorities said a ban was "a necessity".
Local leaders have described their actions as appropriate and proportionate.
But the bans are not just a response to a spate of deadly jihadist attacks on French soil. France has long-standing laws on secularism, and the Nice ban focused on "correct dress, respectful of accepted customs and secularism, as well as rules of hygiene and of safety in public bathing areas".
The Council of State is expected to take 48 hours to deliver its verdict, but the interior minister has said there is nothing to stop mayors taking action, as long as it is "rigorously proportionate".


Off-centre road markings on a Sheffield street are to be repainted following a petition from residents claiming they were dangerous.

The lines on Sandygate Road were painted last year after the road was resurfaced.
Sheffield City Council said the lines were introduced for safety reasons, including improving the safety of cyclists riding up the hill.
The authority said the lines would be changed "as soon as possible".
In a statement, Labour councillor Tony Downing said: "Following the introduction of the new road markings last autumn, we listened to comments made by the public and agreed to carry out a Road Safety Audit on this part of the scheme instead of waiting until June when the whole scheme for the zone has been completed.
"The audit recommended that the central road markings should be restored.  There were issues mainly around vehicles parked on the downhill section of the road, visibility and the increased likelihood of opposing vehicles coming into conflict."
Marie Biggs, who ran the campaign to have the lines re-painted, said she was "very pleased".
She said: "If it's not broken then why fix it? It worked perfectly well with the lines in the middle all the years that I've lived here, so why change it?"


A student who became locked inside Brighton University overnight was let out after a social media plea from her mother was picked up by celebrities.

Emily Rycroft, from Grimsby, became stuck in the building on Monday evening after going inside to collect an essay.
The 21-year-old told her mother who tweeted Radio 2 stars Jo Whiley and Jeremy Vine.
After the DJs retweeted the plea, a key holder was found and she was let out after a couple of hours.
Ms Rycroft, who is studying philosophy, politics and ethics, said: "I was going home from my boyfriend's house and I thought I would stop and pick up an essay that had been handed back in.
"I thought I'd nip to the toilet downstairs, had five minutes to spare before they closed up, but I think someone fancied going home early.
"They had locked the doors and must not have heard or seen me come in. I rang my mum and she thought I was joking."
Her mother, Gillian, set about tweeting the celebrities whose retweets were seen. Security staff then let Ms Rycroft out of the building
"It was amazing [to be let out] - so nice to feel the air again," she said.
A university spokesman said: "As soon as our security staff were informed of the incident they attended and released the student.
"The building was being locked a little earlier than usual and we apologise for any distress this may have caused the student and her family."


The BBC has been shown evidence apparently corroborating reports of a chemical attack in Syria last month.

A BBC correspondent who visited the northern town of Saraqeb was told by eyewitnesses that government helicopters had dropped at least two devices containing poisonous gas.
The government has vehemently denied claims it has used chemical agents.
The US had warned that such a development would be a "red line" for possible intervention.
President Barack Obama said the US had seen evidence of chemical weapons being used in Syria - but it was important to get more specific information about what happened.
In a meeting with Turkish Prime Minister Recep Tayyip Erdogan in Washington, he said all options, both diplomatic and military, were being considered.
The two leaders reaffirmed their support for Syria's opposition and their demands for President Bashar al-Assad to stand down.
"There's no magic formula for dealing with an extraordinarily violent and difficult situation like Syria's," Mr Obama said.
"If there was, I think the prime minister and I would already have acted upon it and it would already be finished."
Meanwhile UK Foreign Secretary William Hague reiterated that Syria must allow access to a UN team to investigate the chemical weapons claims.
By Ian PannellBBC News
Is Syria using chemical weapons?
On 29 April, Saraqeb, a town south-west of Aleppo, came under artillery bombardment from government positions.
Doctors at the local hospital told the BBC's Ian Pannell they had admitted eight people suffering from breathing problems. Some were vomiting and others had constricted pupils, they said. One woman, Maryam Khatib, later died.
A number of videos passed to the BBC appear to support these claims, but it is impossible to independently verify them. Tests are being carried out in France, the UK and Turkey on samples from the site of the attack.
Mrs Khatib's son Mohammed had rushed to the scene to help his mother and was also injured in the attack.
"It was a horrible, suffocating smell. You couldn't breathe at all. You'd feel like you were dead. You couldn't even see.  I couldn't see anything for three or four days," Mr Khatib told the BBC.
A doctor who treated Mrs Khatib said her symptoms corresponded with organophosphate poisoning and that samples had been sent for testing.
One device was said to have landed on the outskirts of Saraqeb, with eyewitnesses describing a box-like container with a hollow concrete casing inside.
In another video, a rebel fighter holds a canister said to be hidden inside the devices. Witnesses claim there were two in each container.
Another video shows parts of a canister on the ground, surrounded by white powder.
Hamish de Bretton-Gordon, a former commanding officer at the UK's Joint Chemical Biological Radiological Nuclear Regiment, said the testimony and evidence from Saraqeb was "strong, albeit incomplete".
In Saraqeb and in three similar events in Syria in recent weeks, "people have got ill and died and their symptoms are what we would expect to see from a nerve type of agent, be it sarin or be it organophosphate," Mr de Bretton-Gordon said.
On the available evidence, recent attacks in al-Otaybeh to the east of Damascus, in Adra near the town of Douma, and in the Sheikh Maqsoud district of Aleppo appear "virtually identical" to what happened in Saraqeb, according to Mr de Bretton-Gordon.
Mr de Bretton-Gordon has not visited the site or tested any of the alleged evidence but was given full access to the material gathered by the BBC.
Both the US and UK have spoken of growing evidence that the Syrian government has used chemical weapons.
Techniques used by investigators include:
How to investigate chemical weapons allegations
Rebel fighters have also been accused of using them. They also have denied this.
In March, Syria's government and opposition called for an inquiry into an alleged chemical weapon attack in Khan al-Assal in the north of Syria which killed at least 27 people, with both sides blaming each other.
A 15-strong UN team headed by a Swedish scientist Ake Sellstrom has been assembled to investigate the claims.
However, the Syrian government has refused the team access. Syrian officials have been quoted as saying they want the team to look into the incident in Khan al-Assal, but the team has requested unconditional access with the right to inquire into all credible allegations.
The UN estimates that the two-year-old conflict has left at least 80,000 people dead.


A 10-year-old boy who has jaw cancer and needs urgent surgery has vanished, a High Court judge has said.

Mr Justice Mostyn made a written order stating efforts should be made to find the boy, whom he said was Polish and could be in Poland with his parents.
He granted an application, made by an NHS trust, allowing doctors to perform surgery on the boy to remove a tumour.
A doctor said the child - who was not named - will die a "brutal and agonising death" without surgery.
Details of the hearing emerged in a ruling following hearings in the Family Division of the High Court in London.
Mr Justice Mostyn said doctors believed the boy, who had lived in England with his parents for two years, was at risk of "serious harm" and the risk was growing each day.
He said there was evidence the boy had left his home with his mother two weeks ago, and that the boy's father had boarded a ferry bound for France in the past few days.
One doctor said the prospect of him growing up was "completely impossible" without surgery.
The paediatric oncologist said the boy's parents were "very frightened and fearful", worrying that he would be disfigured by surgery and preferring to treat him with "Chinese medicine".
Surgery could last as long as 12 hours and would require skin and bone from the boy's leg to rebuild his jaw bone, the judge said in his ruling.
It could result in "lameness", would leave the boy needing false teeth, and he could develop a "lopsided appearance", he added.
Mr Justice Mostyn stated: "I give full weight to the wishes of (the boy) as well as those of his parents.
"It is a strong thing for me, a stranger, to disagree with and override the wishes of (the boy) and his parents.
"But I have absolutely no doubt that (the boy) must be given the chance, a very good chance, of a long and fulfilling life rather than suffering, quite soon, a ghastly, agonising, death."
Mr Justice Mostyn said the Polish embassy in London was being alerted of the need to find the boy.
The judge referred to the boy and his parents by initials only and did not name the NHS trust.


British sailors won two golds on the first day of medal racing at the Sailing World Cup Miami.

Dylan Fletcher-Scott and Stuart Bithell won the 49er class by finishing fifth in their final race of the regatta.
Ben Saxton and Nicola Groves had earlier triumphed in the Nacra 17 class, beating compatriots Tom Phipps and Nicola Boniface into second.
Miami, the first leg of the 2017 World Cup series, is the first regatta since last year's Rio Olympics.
Bithell and Fletcher-Scott, who was sixth alongside Alain Sign at Rio 2016, are a new pairing.
"It feels like we've gelled pretty well," said Bithell, who won silver at London 2012 in the 470. "There's still plenty of work to do, but it's nice to be on top of the podium."
Find out how to get into sailing with our special guide.


Three million people will have particular reason to listen in to the Spending Review and Autumn Statement on Wednesday, as the chancellor announces what is to become of his plans to cut working tax credits.

They are the claimants, who, according to the Institute of Fiscal Studies (IFS), stand to lose an average of £1,000 a year from April 2016.
After losing a vote in the House of Lords, the chancellor, George Osborne has promised to soften the transition to lower tax credits, but without losing sight of the £4.4bn in eventual savings to the Treasury.
So what are the chancellor's options, and how will those three million people be affected?
Eventually tax credit payments will get smaller anyway, as claimants switch to Universal Credit. But any postponement of the cuts would reduce the £4.4bn in annual savings. So either the chancellor would need to find large cuts elsewhere, or the Treasury would have to live with the deficit beyond 2020. Currently the Office for Budget Responsibility (OBR) is predicting a budget surplus by then.
If the cuts are reduced, the chancellor will need to be careful not to break the government's self-imposed welfare cap, which limits the amount of total benefit spending, and which comes into force in April 2016.
Tax credits are nothing to do with paying tax. They are a series of benefits introduced by the last Labour government to help low-paid families. There are two types: Working Tax Credit (WTC) for those in work, and Child Tax Credit (CTC) for those with children. Tax credits are gradually being included within Universal Credit, which is being rolled out across the country.
The idea of this benefit is to encourage people to work. As an example, most people will need to work at least 30 hours a week to qualify. If you have children, are under 25 or over 60, you will need to work 16 hours a week.  You can earn a maximum salary of £13,253. Currently claimants earning less than £6,420 receive the full entitlement. As they earn above this level, their payments are reduced.
To qualify for CTC you need to have at least one child, but you don't need to work.  As an example, those with one child can earn up to £25,000 and still qualify for a payment. For those also claiming WTC, anyone earning less than £6,420 (the income threshold) will receive the full entitlement. For those not claiming WTC, they can earn up to £16,105 before seeing a reduction in their payments
The income threshold for Working Tax Credits - £6,420 - is due to be cut to £3,850 a year. In other words, as soon as someone earns more than £3,850, they will see their payments reduced. The income threshold for those only claiming CTCs will be cut from £16,105 to £12,125. Osborne could tweak these thresholds.
The rate at which those payments are cut is also due to get faster. Currently, for every £1 claimants earn above the threshold, they lose 41p. This is known as the taper rate. But from April 2016, the taper rate will accelerate to 48p. So for every pound earned above the threshold, claimants will lose 48p. Again, Osborne could tweak the taper rate.
There are due to be similar reductions for those who claim work allowances under Universal Credit.
Who will be the losers?
The IFS has said that three million families are likely to lose an average of £1,000 a year, as a result of the previously announced changes to tax credits.
But the government has argued that the introduction of the National Living Wage (NLW) will raise incomes for many people when it is introduced in April 2016.  New personal allowance thresholds will also mean many people will pay less income tax.
The Resolution Foundation - which campaigns for low and middle-income families - has analysed all the changes, taking into account the NLW and new income tax thresholds.
It claims that by 2020, a low-earning single parent, with one child, who works 20 hours a week, and who earns £9.35 an hour, will end up £1,000 a year worse off.
A low-earning couple with two children, also on £9.35 an hour, will be £850 a year worse off. However, a childless middle-earning couple will be £350 a year better off, as a result of the new personal tax allowance.
Chancellor George Osborne says that anyone who is working full-time on the National Living Wage will be better off, after the tax changes are taken into consideration. However most people claiming tax credits are likely to be working part-time.
The amount anyone can earn before having to pay income tax - the personal allowance - rises to £11,000 in April 2016, with the aim of reaching £12,500 by 2020.
The Treasury says higher income tax thresholds have saved basic rate taxpayers £825 a year each since 2010, with 3.8 million people taken out of the tax system altogether.
The government is also doubling the amount of free childcare available to working parents of three and four-year olds, from 2016. It says 600,000 families will benefit. It will be worth an extra £2,500 a year.
The actual level of tax credits, along with all working-age benefits, will be frozen until April 2020. This is scheduled to save another £4bn. If inflation were to continue at its current level of zero, the effect on claimants might be minimal. But inflation is expected to rise again to the target rate of 2% within two years. However, Osborne is unlikely to row back from this commitment, as it is a freeze rather than a cut.
Nevertheless, analysis by the IFS suggests that those in work, but receiving low salaries, will be hardest hit by the changes.
The calculations were made before taking into consideration the forthcoming NLW, or tax changes.
As the chart above shows, those in the second poorest category of workers are likely to lose more than £1,200 a year. By contrast, the richest 10% stand to lose less than £400. Only those in the ninth richest category will gain.
In a subsequent analysis, the IFS said the NLW would go 26% of the way to compensating working households for the forthcoming loss of benefits. But it said households with someone in paid work would still end up £550 a year worse off, on average.
From April 2017, those starting a family will no longer be eligible for the family element of tax credits - for CTC, that is £545. The equivalent in Universal Credit, known as the first child premium, will also not be available for new claims. In addition, new tax credit claims will be limited to two children. In other words no allowance will be made for a third or fourth child.
The government has insisted that no existing claimants will lose money as a result of this change. Again, Osborne is unlikely to change this.
The Resolution Foundation says a family with three children, making a claim after April 2017, could be £3,450 a year worse off than under the current system.


If walls could talk, the iconic Guildhall in Carmarthen would have some colourful stories to tell.

The court building has been at the centre of some of the most momentous events in Welsh history during its 250-year lifetime.
Gwynfor Evans' landmark victory as first Plaid Cymru MP was announced from its balcony in 1966 - an event which changed the face of politics in Wales forever.
And the court played a pivotal role in the Agrarian 'Rebecca Riots' in 1839-43 when some of the ringleaders were sent to transportation directly from there.
Carmarthen also attracted the national spotlight when Ronnie Harries, one of the last men to be hanged in Wales, was sentenced to death there in 1953 after murdering his relatives Phoebe and John Harries at their home, Derlwyn Farm, in the hamlet of Llangynin.
But despite this rich history, the future of the Grade II listed building looks uncertain.
On Friday, magistrates will retire for the final time as it is one of 10 Welsh courts earmarked for closure by the Ministry of Justice.
For those who have played a part in the court's story, its closure raises serious concerns about the impact it will have on the town.
Carmarthenshire councillor Alun Lenny, who is also a former BBC and Carmarthen Journal reporter, recalls: "As a journalist in the 1970s I sat through literally thousands of cases in the Guildhall over a period of 30 years, for the Journal, TV and radio.
"I remember a time when the magistrates sat for at least two full days a week and the crown court for a week or two every month.
"The crown court in the Guildhall is like a miniature House of Lords and is an iconic building smack in the centre of town.
"It is one of Carmarthen's most prominent buildings and I really hope it can be turned into a heritage and history centre and isn't lost to the people of Carmarthen."
Court closures in Wales- full picture
The court's role in local history is indisputable but in 1966, the national spotlight shone there when Gwynfor Evans won the Carmarthen by-election.
He held the seat twice, eventually losing it in 1979, and also threatened to starve himself in the cause of Welsh language television, leading to the foundation of S4C.
About 2,000 people gathered in the square outside Carmarthen's Guildhall for his shock victory.
One of them was The Reverend Towyn Jones, president of the Carmarthenshire Antiquarian Society and a local historian who moved to the area 41 years ago.
He said: "The atmosphere was electric at times, people were working themselves up into a frenzy and chanting his name. It was pretty intense, like being in some voodoo ceremony."
Mr Lenny also recalls covering one of the court's most high-profile cases in 1978 when Rhodri Williams and Wynfford James from the Welsh Language Society or Cymdeithas Yr Iaith Gymraeg were tried for conspiracy to damage a TV transmitter during their campaign for a Welsh TV channel.
"The place was packed, with hundreds of demonstrators both in and outside," remembers Mr Lenny.
"The court case resulted in the pair being imprisoned but there were also numerous contempt of court charges throughout as people interrupted proceedings or banged on the windows from outside."
Mr Lenny was present at the remand hearing for the prolific burglar and serial killer John Cooper, from Milford Haven, who was convicted in 2011 after a cold case review linked him to the double murders of brother and sister Richard and Helen Thomas at their house in Pembrokeshire in 1985.
In 1989 Cooper also confronted holidaymakers Peter and Gwenda Dixon, aged 51 and 52 and from Oxfordshire, on the Pembrokeshire coastal path near Little Haven and shot them at point blank range after demanding their pin numbers and later raiding their bank accounts.
He was also convicted of separate charges of rape, sexual assault and attempted robbery and jailed for life.
Mr Lenny said: "I vividly remember Cooper shouting at me and the cameraman that he was not guilty. The jury disagreed."
As there is no existing interpretative centre for the Rebecca Riots in west Wales, Mr Lenny believes the court building could fill that gap, becoming a tourist attraction and education centre for local school children with audio-visual displays and exhibitions.
Or it could serve as a branch for the county museum at Abergwili, with 'rolling' displays of artefacts.
He also recalls that at one time the tiny adjacent pub, The Plume of Feathers, had a door that opened directly into the magistrates' private rooms.
Mr Lenny said: "The magistrates would retire and you would pop round the corner into the Plume of Feathers and you would buy the magistrates a beer and negotiate your punishment. This was back in the 19th century - I couldn't see it working now, but I have seen the door with my own eyes."
Bryn Jones, now 85, was one of the police officers who escorted Ronnie Harries back and forth to the court from Swansea prison during his notorious trial.
Harries was accused of bludgeoning his aunt and uncle to death with a hammer and burying them in a field. He was the last but one man to be sentenced to hanging from the court and was executed inside the prison.
Mr Jones, who served with Dyfed-Powys Police for 38 years and retired as a Ch Supt in 1988, said: "From 1952-55 I was a traffic officer in Carmarthen. In those days we didn't have security firms ferrying people back and forth from court to prison.
"Ronnie Harries was being held in Swansea prison and he had to appear in court every four days and then be taken back again to his cell.
"I know it's a strange thing to say about a convicted murderer but believe it or not he was a very pleasant sort of person, always very chatty in the car.
"One thing I remember is that he said to me and the other officers 'Boys when this is all over, I will take you out for a slap-up meal". Well that never materialised.
"He was talking all the time and acting in a normal way.
"He had a quite a reputation with the ladies and I can well understand that because there was a certain amount of charm about him."
There are various myths about how police caught Harries - from officers stretching cotton across gateways near the farm to check which lengths had been broken and thus pinpointing where the bodies would be found to a buzzard perching on a fence pole near their makeshift grave.
But Ronnie Harries' cousin, Lynn Hughes, is a local historian who recalls how the bodies were discovered by a police officer he knew personally after a search of a nearby kale field.
He said: "Sgt Phillips of Llandeilo noticed that the crops in one particular area of the field were not prospering and ordered the area to be dug up."
Mr Hughes recalls that his older cousin was a "spoilt only child, who had to have everything he wanted right away".
"My father used to race motorcycles in Pendine Sands and we used to call in on Ronnie and his parents, Muriel and John, on the way back for tea.
"He wanted this USA motorbike and had a terrible accident on it where he jumped off one of the narrow lanes and suffered a severe head injury. However, this wasn't taken into account at his trial.
"The motorbike was abandoned and then he had one of the first Land Rovers in Carmarthenshire. He was so persistent, he wore his parents down.
"I remember him taking me for a drive in it and feeling very uncomfortable in his company. He definitely had mental health issues and in modern times would have been sent to an institution rather than be hanged for what he did.
"I didn't go to the trial as I was just a boy of seven and he was a man in his 20s, but I do remember the devastating impact it had on my aunt and uncle."
Mr Jones told how people were perched on top of local buildings for the Harries verdict, such was the local interest in the case.
"When the judge put his black cap on, there were people in the window putting their thumbs down to signify that Harries was to be hanged."
He has also researched and written about the part the court played in the sensational 'Kidwelly case' in 1920 when solicitor Harold Greenwood went on trial there for poisoning his wife Mabel with arsenic.
Greenwood was largely believed to be guilty by the local community but was cleared due to the defence and skilful cross-examination of his wife's doctor by his star QC, Marshall Hall.
Mr Hall raised the possibility that Mrs Greenwood had died from an accidental overdose of morphine. His closing speech for the defence was described by the author Gerald Sparrow as "the finest ever heard at the English bar".
Mr Hughes said: "His speech in mitigation is famous in Welsh legal history and the case was the best-known in the Carmarthen court's history.
"The court was packed for the trial, with spectators arriving by the trainload to hear the arguments."
Mr Jones added: "Emlyn Thomas, a former editor of the Carmarthen Journal, now deceased, was a young reporter during the trial and I remember him telling me it was doubtful because of Marshall Hall's health if he would be able to give his closing speech the following day.
"However, he spoke for almost three hours and was totally brilliant. He quoted Othello more than once during the trial and everybody was transfixed, but Greenwood was furious when Mr Hall left court.
"The only person to leave court at the same time was Emlyn Thomas who chased after him.
"I can only tell you what he told me and that was that when he caught up with Mr Hall somewhere around Queen Street, he asked if Greenwood was guilty or not guilty and according to Emlyn, Mr Hall replied: 'he's as guilty as hell' and off he went.
"Imagine the cheek of questioning the defence counsel like that!"
Another famous poisoning case which took place at the court was that of cook Betsy Gibbs in 1851. She was accused of poisoning her mistress Mary Ann Severne of Brixton Farm, Laugharne and Mrs Severne's maid, Rebecca Uphill.
In September 1850 Mrs Severne's body was exhumed and the coroner confirmed that their deaths were due to arsenic poisoning.
Newspaper reports from the time cite a wealth of eyewitness evidence against Ms Gibbs, but the packed public gallery was dumbfounded when the jury returned a not guilty verdict.
The Reynolds Newspaper of 13 April 1851 reported that she was targeted by a mob of angry locals when she returned home to Laugharne: "This circumstance still further aroused the popular indignation, and on the night of the 27 Gibbs's effigy was duly suspended upon a gallows, which was erected in front of her dwelling, and afterwards set fire to, amid the exultation of the mob.
"On the following evening a lengthened mock funeral procession paraded up and down the street where Elizabeth Gibbs resided, which, by the bye, has had its cognomen metamorphosed into that of 'Scape-the-Gallows-Street.
"These reiterated annoyances induced her to leave the town, and accordingly she passed through Carmarthen on her way to Merthyr, again exciting the disgust and indignation of a tumultuous assemblage, who crowded to satiate their curiosity by gazing on the woman whom the law had pronounced innocent of the murders which excited their horror."
Over the past 10 years, the crown court has gradually faded away from the town, with the crown cases transferred to Swansea and the magistrates cases transferred to Llanelli.
The recent closure announcement has prompted magistrate and former Carmarthen mayor Richard Goodridge to resign.  His association with the court goes back 40 years as his father Stan used to be hall keeper and as a boy he used to go and open up and close with him.
Mr Goodridge, 55, said: "If you look back at the history of the Magna Carta, the whole purpose of the magistrates' courts was that people would be tried by their peers within the locality.
"What they are looking at now is people being tried by computer to save costs, which changes the whole ethos of being brought to court.
"The principle of having to attend court in front of people to answer for your crimes is a big deterrent and being lectured on your wrongdoings by a magistrate is part of that deterrent. It not being done any more will have a big impact. "
Mr Goodridge said that he has resigned from the bench for his own safety.
"I don't have a car and I don't want to travel on the bus or the train to Llanelli and risk sitting in front of somebody whose case I will be hearing," he said.
"There will be cases where witnesses are standing on the same train platform as the people they are giving evidence against and that can't fail but have an impact for justice."
Mr Goodridge believes the court should be handed back to the people of Carmarthen as it was originally transferred free to the court service.
He is also concerned about what will happen to the three bronze bells that the town's late chemist Gwynne King Morgan donated to the people of Carmarthen which were installed in the late 80s and early 90s.
He added: "Cardigan, Newcastle Emlyn, Llandovery, Ammanford, Whitland, St Clears, Narberth, Haverfordwest, and others have all had their court buildings closed and sold off to the highest bidder, many since falling into disrepair. This must not be allowed to happen here.
"It's been a travesty of justice and a justice that no longer exists in the local community."
Juliana Hughes, a magistrate in the area for 25 years, who has since retired, said: "It's a really beautiful court which adds to the dignity of the court proceedings and the seriousness of the hearings.
"I've sat in Llanelli several times and it just doesn't have the same feel to it," she said.
"It will take away the idea of local justice which was the main idea behind magistrates' courts, that local justice would be administered by local people.
"It's changed the whole ethos of the magistrates' courts and it's becoming a sphere where the people who practice the law are the only people who have any say."
Mrs Hughes has seen many smaller courts close in her time, including St Clears which was once a miniature version of the Carmarthen court and used to be attached to the police station.
The century-old police court house in Bargoed, near Caerphilly, closed in 1997 but is now a town hall, while a new family-run supermarket is to be built on the site of the former Barry Magistrates' Court, creating 40 jobs in the town.
The operating costs for Carmarthen Law Courts were approximately £162,000 for the financial year 2014-15.
The Ministry of Justice argues that public transport links are good and regular local bus services link Carmarthen to local population centres.
It says that Llanelli is a multi-jurisdictional court, which has the capacity to accommodate Carmarthen's criminal workload.
It also argues that the court building is not compliant with the Equality Act 2010 and there is inadequate separation of victims, witnesses and defendants, inadequate judicial and juror segregation, with poor facilities for witnesses and victims.
Due to the absence at the site of a modern vehicle dock, prisoners are delivered to the building via the public pavement outside of the premises.
Justice Minister Shailesh Vara said: "Our courts and tribunals system is in need of urgent reform. Maintaining our underused and dilapidated court buildings costs the taxpayer £500m million a year but some courts sit for less than half the time available.
"This is simply unsustainable. Closing these courts in poor quality buildings will raise £40m to re-invest in the justice system, and save hard-working taxpayers £27m per year.
"The decision to close a court will never be taken lightly, but in the digital age I am confident we have measures in place to ensure access to justice is not diminished."


Last summer, when filming for a series to be broadcast next year, a team from the BBC's Natural History Unit saw first-hand how discarded plastic can end up thousands of miles away from where people live when they visited French Frigate Shoals, an island north west of Hawaii.

There they found turtles nesting amongst plastic bottles, cigarette lighters and toys. And they discovered dead and dying albatross chicks, unwittingly killed when their parents fed them plastic carried in as they foraged for food in the sea.
Some of the chicks die when sharp edges puncture their bodies, others from starvation as their stomachs fill with plastic they cannot digest.
We have known for a while that plastic is a threat to the albatross, but how dangerous is discarded plastic for other wildlife and could it affect us?
Some of the plastic in our oceans has been illegally tipped at sea, or is litter from fishing, most comes from the land, from poorly run landfill sites and industrial waste.
Floating debris is carried to the Hawaiian archipelago by giant rotating ocean systems, or gyres, partly driven by air currents.
Hawaii sits in the midst of a gyre known as the North Pacific Sub-tropical High. The North Pacific gyre is one of five gigantic interconnected systems of ocean currents. Each spirals around a central point, drawing material inwards.
These spirals can also eject material, out towards the Arctic and Antarctic, spreading plastic across the globe over time.
Plastic is made to last, so it decays only very slowly in the oceans, breaking down into ever smaller fragments. These tiny fragments are known as micro-plastic.
Dr Simon Boxall is an expert in marine pollution based at the National Oceanography Centre in Southampton, on Britain's south coast. We took a boat trip with him in the sea near his research centre.
Using a simple net and bottle system, the boat filtered roughly 400 tonnes of water in 10 minutes. With the naked eye we could see mud, twigs and a few feathers, but when we looked at the sample under the microscope in Dr Boxall's laboratory tiny pieces of plastic became clear.
The sample included small pieces of plastic rope and plastic bag, some fragments were distinctly coloured and some had sharp edges. There were pieces less than a millimetre across, similar in size to the living things in our sample - the phytoplankton, or tiny plants, and zooplankton, or tiny animals.
"There's been a lot of research in the United States looking at how the plastic gets into the food chain, and certainly it's been shown that it gets into bi-valves, mussels and oysters on the seabed, and it does have an effect on them," Dr Boxall said.
"They bio-accumulate the plastic as they filter the water. That concentrates the plastic and effectively turns some of those molluscs into hermaphrodites. Some years ago it was assumed that it was like roughage, and didn't have a major impact, but we know now that those very small plastic particles can mimic certain things like oestrogen," he added.
However, he said the true effects are not yet known:
"These plastic particles are like sponges, they're a bit like magnets for other contaminants, things like Tributyltin, the anti-fouling material. The tiny plastic particles absorb these materials and effectively become quite toxic. We don't know yet whether that then has an impact on the human food chain. It's still very early days to find out how far up the food chains these plastic particles go."
At the Marine Biology and Ecology centre of Plymouth University they study the impact of pollutants on our oceans and rivers, and the creatures that live in them. Marine scientist Professor Richard Thompson was the first to describe the tiny fragments of broken plastics as micro-plastics back in 2004.
"There are two concerns from a toxicological point of view. There's the issue that plastics are known to sorb and concentrate chemicals from sea water," he explained.
"And the secondary question is about chemicals that have been introduced into plastics from the time of manufacture, in order to achieve specific qualities of the plastic, its flexibility, or flame retardants or anti-microbials.
"When we've now got plastic not as whole intact items but as small fragments in the environment, is there the potential for any of those chemicals from manufacture to also be released?"
Prof Thompson's team has been examining fish in the English Channel, 500 or so across 10 species - including mackerel, whiting, poor cod and gurnard.
His results have just been published in Marine Pollution Bulletin (Lusher et al, MPB, December 2012). The team found microscopic plastic in the guts of all of the species tested.
"It's showing that micro-plastics are quite widespread in the environment, not just in the water columns and the beaches, but actually in the creatures that live in those environments," he said.
Prof Thompson said the plastics had been found "in relatively low quantities - one or two pieces per fish - so this is certainly not a risk from the point of view of the human population, people eating those fish, because of course we don't eat the guts normally".
"The question we do want to address is is that a problem from the point of view of the animals concerned, in individuals that are eating plastic, either from the point of view of the physical presence of the plastic, or the potential for chemical transport?"
I asked if that means there is a concern for people who eat the flesh of the fish, if those chemicals have found their way into the animal.
"It's really an unknown," Prof Thompson said.
"The next step is to take the information like that from fish and other creatures to understand how much plastic, what are the chemicals that might be of concern... what are the concentrations of those chemicals, what are the quantities of plastic, and how does that vary from species to species in order to understand which particular combinations might create the greatest potential for hazard...
"That's what our work is trying to establish at the moment - what potential is there for these micro-plastics to actually cause harm in the real world."


A Ukrainian officer has defied a Russian court trying her over the killing of two Russian journalists, vowing to continue a hunger strike and making an obscene gesture at judges.

Nadia Savchenko, a pilot who served as an infantry volunteer fighting rebels, was making her closing statement.
She denies directing mortar fire at the Russian journalists in June 2014.
She says she has not had food and drink since Friday.
Speaking Ukrainian, she mocked the judges in the court in the south Russian town of Donetsk, saying they proved that Russians were "fascists".
A translator read out her formal, final statement in which she proclaimed her innocence and described her trial as a "farce".
The EU and US have both called for her immediate release.
A verdict in the case is due to be delivered on 21 and 22 March but her lawyers have said she will not survive that long unless she is force-fed.
If convicted, she could face 20 years in prison.
This was a brief hearing but a dramatic one. Despite five days refusing food and water, by her own account, Nadia Savchenko walked into court herself and stood throughout - her cage surrounded by armed guards.
When she spoke, her voice was strong - and angry. At one point she leaped on to the bench and showed the three judges her middle finger - a furious demonstration of what she thinks of Russian justice.
Her formal statement was read by a translator, in which she called President Vladimir Putin a "tyrant" and her trial a "farce" directed by the Kremlin.
Some supporters had brought yellow flowers, to match the Ukrainian flag, and as the judges left to consider their verdict over the next 12 days, Nadia Savchenko stood with her hand on her heart leading them and her relatives in a passionate verse of the Ukrainian national anthem.
She vowed to keep up her hunger strike until she is returned home. But outside court, her lawyers warned that she would not live that long unless she was force-fed.
How Savchenko became a symbol of resistance
She was captured in the summer 2014 at the height of the fighting between Ukrainian troops and pro-Russian rebels.
A pioneering female combat pilot in the Ukrainian air force, where she held the rank of lieutenant, she had enlisted in a volunteer infantry unit, the Aidar Battalion, to fight in eastern Ukraine.
She is charged with acting as an artillery spotter and directing the bombardment of a rebel checkpoint, in which two Russian state TV journalists, Igor Kornelyuk and Anton Voloshin, were killed.
Denying the accusation, the 34-year-old insists the whole case against her is politically motivated, and she has become a symbol of Ukraine's resistance against Russia.
She says she was kidnapped by rebel fighters at least an hour before the attack in which the Russian journalists were killed, and later handed over to the Russian authorities.
Russian prosecutors say she secretly crossed into Russian territory herself.
Ukrainian diplomats in the Russian region of Rostov say judges in the case are refusing to issue any more permits to visit Ms Savchenko in prison.
Her relatives have also used up all their visiting permits, meaning a group of Ukrainian doctors en route from Kiev to visit her will also not be given access.
The EU has expressed concern about Ms Savchenko's wellbeing, and Nobel prize-winner Svitlana Aleksievich is among more than 4,300 signatories to an open letter urging European leaders to act to secure her freedom.
Relations between Russia and Ukraine - along with its Western allies - have deteriorated since the events of 2014 in Ukraine.
Moscow annexed the Crimean peninsula that March after an unrecognised referendum on self-determination, and is accused of covertly supporting the rebels in the bloody conflict which later divided eastern Ukraine.


Manchester City lost ground on Premier League leaders Leicester City as Sergio Aguero scored twice to rescue a draw at West Ham.

Enner Valencia struck from inside the area after 53 seconds for the Hammers but Aguero equalised with a penalty after he had been fouled.
The hosts retook the lead when Valencia capitalised on hesitant defending by Nicolas Otamendi to stab in.
However, Aguero struck from 10 yards late on to earn his side a point.
The result means Manchester City are second, three points behind Leicester, while West Ham are sixth.
Read about how the game unfolded
Reaction to all of Saturday's Premier League action
Football Daily Podcast: Premier League round-up
Of the sides in the top three, Manchester City boast the worst away record.
They have won just four games on the road all season, while their last five away trips have seen them pick up just six points from a possible 18, a far from ideal record for a side challenging for the title.
Against West Ham, it was their inability to complete the basics of defending that was of particular concern.
They switched off in the first minute to allow West Ham to score, but their defending for the hosts' second was particularly poor.
Michail Antonio's quick throw initially caught out Otamendi, but he still had the time to be able to clear before Valencia nipped in to poke home.
Luckily for City they had Aguero to rescue them, but with away trips to struggling Sunderland and Newcastle coming up, Pellegrini's side can ill afford such lapses in those games.
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After a strong start to last season West Ham dropped away at the turn of the year, winning just three more Premier League games.
The Hammers were similarly impressive in the first half of the current campaign but, crucially, they look capable of continuing that through the second half of the season this time.
They had won three of their four games in 2016 prior to the visit of Manchester City, and boast an impressive record against top seven sides, having lost just twice to the sides around them.
In Dimitri Payet they have one of the most exciting player in the Premier League and he tormented City throughout, with only a world-class save from Hart denying him a goal.
With West Ham six points behind fourth-place Tottenham, a top-four finish might be a tough ask, but their recent form suggests they will be prompting a few nervous glances over the shoulders of their rivals.
There has been plenty of uncertainty about Yaya Toure's future in the newspapers this week, but City boss Manuel Pellegrini has urged the midfielder to concentrate on helping his side challenge for the title.
Pellegrini clearly felt Toure is fully focused on the task at hand as he recalled him for the trip to West Ham, but he was sluggish at the start.
He was left woefully wanting when Cheikhou Kouyate ghosted past inside a minute to set up Valencia for the opener.
In the end, Toure had more touches of the ball than any other City player, but struggled to make a telling impression in the opposition half, with only defenders Fernando and Otamendi having a poorer passing accuracy than the midfielder.
West Ham manager Slaven Bilic: "It was a great game of football. I'm so proud of our team and Man City. There was everything in it. Four goals, chances, yellow cards and a penalty.
"We were a little bit disappointed, but I said to the players they shouldn't be. But if you are disappointed after playing Man City then that's good.
"We defended well and created many chances."
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Man City manager Manuel Pellegrini: "It [a draw] was not what we wanted before the game. If you analyse the whole game we had two or three clear chances. It was a difficult game - I was not happy the way we conceded the second goal.
"It was a close game for both teams and a good game for both sets of fans. It was end to end because both teams play in an attacking way.
"Sergio Aguero played very well and scored. I think he is 100% again."
West Ham are in FA Cup fourth-round action at Liverpool on 30 January while Manchester City's next game is against Everton in the League Cup semi-finals on 27 January.


Labour has protested after the Conservative press office tweeted the names of MPs it said "won't respect the referendum result".

One Labour MP called on the PM to disown the tactic while pro-EU Tory Anna Soubry said she had complained to her party's chief whip.
It comes after MPs overwhelmingly backed ministers' Brexit timetable.
Twenty three Labour MPs voted against the motion, and about 100 MPs from both sides of the Commons did not vote.
The tweets accused 14 Labour MPs, none of whom appear to have voted in the debate, of being "out of touch with ordinary working people".
One of those named - Pat McFadden - called on Theresa May to condemn the behaviour.
He said: "The prime minister should disown this activity and make sure it doesn't happen again.
"It is unhealthy for our democracy to elect MPs to be attacked in this way for expressing their views."
But UKIP MP Douglas Carswell said this comment was "farcical", saying a Labour MP had attacked him during the debate "for being UKIP".
However, another Labour MP, Ben Bradshaw, described the naming of individual MPs as "disgraceful" and "straight out of the Donald Trump playbook".
Ms Soubry added: "It's completely out of order. The party need to back off."
Another pro-Remain Conservative MP, Neil Carmichael, called on ministers to "reach out" to critics.
BBC assistant political editor Norman Smith said former Tory chancellor Ken Clarke, the only Conservative to vote against the government motion, received abusive emails on Thursday morning.


At her art therapy class in Leeds, Joyce Cope is carefully painting a tree.

Despite living with dementia, her brushstrokes are measured and steady, the legacy of her years of painting as a talented amateur.
Her work today is very different to the highly detailed pieces she used to produce - expert reproductions of Old Masters such as "Girl With the Peal Earring" by the 17th century Dutch artist Johannes Vermeer.
Joyce's daughter, Hazel, says her mum still enjoys painting, but before the disease took hold her work was really striking.
"They were really good copies of the Old Masters and very detailed.
"She's not as detailed now.
"She can remember things from years ago, but generally if you asked her what she had for breakfast this morning she can't remember."
But can art - more specifically, the way artists work - tell us something about the development of dementia and other degenerative brain diseases?
A minute analysis of the brushstrokes used by artists who developed neurological diseases reveals intriguing clues about changes in the brain that occurred years before any symptoms became obvious.
The mathematical method is called "fractal analysis", which is a way of looking at recurring patterns that occur both in maths and in nature.
Trees and clouds are said to be "fractal", as are the recurring patterns of our brainwaves and heartbeats.
The same applies to the individual brushstrokes of artists, which can be compared to their individual handwriting.
Psychologist Alex Forsythe from Liverpool University carried out a fractal analysis of more than two thousand works by seven famous artists and found tiny changes in those patterns.
"In artists who went on to develop dementia or Parkinson's disease, the fractal patterns started to change in an unusual way.
"So what we found was that up to 20 years before they actually had a diagnosis of a neurological disorder, the fractal content in the paintings had started to decrease.
"So anything that helps us understand more about the way in which the brain operates is a useful way to inform future directions for research."
The artist Willem de Kooning was diagnosed with Alzheimer's disease after his death in 1997.
The brushstroke patterns seen in his earlier work were different when compared to later paintings.
But in artists like Monet and Picasso, who died free of any known neurological disease, the patterns remained constant throughout their lives.
It's striking that the even though Picasso in particular changed styles so often throughout his career, his fractal range was constant, regardless of the style in which he painted.
This research won't help diagnose dementia or similar diseases.
But it does give a valuable insight into changes that are taking place in the brain years before the illness appears and so could help provide some answers to the hidden processes behind these devastating conditions.


Rolls-Royce has said that it is in talks with the Serious Fraud Office over possible bribery and corruption.

"It is too early to predict the outcomes, but these could include the prosecution of individuals and of the company," the British firm said.
The aircraft engine manufacturer said it had passed on information about alleged malpractice by intermediaries.
It followed a request from the SFO for information about possible bribe-paying in Indonesia and China.
The BBC understands that the request prompted Rolls-Royce to bring in a legal firm to conduct an internal investigation earlier this year, which uncovered potential misbehaviour in other countries as well as the two named by the SFO.
The "intermediaries" involved are local companies that provide sales and distribution, and repair and maintenance services for Rolls-Royce in countries in which the UK firm does not have enough of its own people on the ground.
Some of the allegations date back more than 10 years. The company was keen to highlight that it has strengthened its internal compliance rules in the last five years, including the creation of a new chief compliance officer role in 2010.
Shares in the company fell 5% at the start of trading in London on Thursday, before partially rebounding.
Rolls-Royce said it was cooperating fully with the investigation.
"I want to make it crystal clear that neither I nor the board will tolerate improper business conduct of any sort and will take all necessary action to ensure compliance," said chief executive John Rishton.
"This is a company with exceptional prospects, and I will not accept any behaviour that undermines its future success."
The company said that it had recently instituted a new ethics code of conduct, and would be hiring an independent consultant to carry out a review of its current procedures.
Rolls-Royce is a major international player in civil aerospace and defence, and employs over 40,000 people in 50 countries.
It is the world's second largest manufacturer of aircraft engines after General Electric.
China and Indonesia were ranked 80 and 118 respectively out of 174 countries in the corruption perceptions index published by Transparency International on Wednesday, ranking from the least down to the most corrupt.
China is Rolls Royce's fourth biggest market, and the firm employs almost 2,000 people in the country, mainly selling civil aerospace and energy industry products.
Indonesia is a relatively small market for the company.
Britain's other major aerospace company, BAE Systems, had to pay fines worth Â£286m in 2010 following investigations in the US and UK of alleged bribe-paying in Saudi Arabia, Africa and central Europe.
Other international companies from the sector to have become embroiled in corruption scandals in recent years include Boeing, General Electric and Siemens.


A police officer has been convicted of raping a woman.

Oxford Crown Court heard how PC Richard Hale, 35, of Peel Place, Carterton, Oxfordshire, attacked the woman in her 20s after they visited pubs together in Witney on 3 December 2001.
She came forward in June 2012 to report the rape, which happened at a property in Peel Place in Carterton.
The Thames Valley officer was remanded in custody for sentencing at the same court on a date yet to be confirmed.
The rape happened two years before Hale joined the force.
Thames Valley Police said all sex offence victims "should feel confident" in reporting incidents regardless of when they happened.
Assistant Chief Constable Jason Hogg said: "There is no place in the force for those who commit offences of this nature."
The force has launched a misconduct investigation following the conviction.


People travelling by rail over Easter should "think twice", Transport Secretary Patrick McLoughlin has said.

He told the Evening Standard large-scale rail engineering work may make journeys more difficult.
Several major rail routes are affected, particularly the London to Scotland West Coast main line, parts of Kent and lines running through Reading.
The RAC says four million motorists will be travelling on Good Friday and some 4.5 million on Easter Sunday.
Arriva Trains says passengers in Wales will face delays if travelling to London due to engineering works.
"There will be alternatives and we've lifted almost all motorway roadworks to help," Mr McLoughlin said.
"But if you are travelling between Friday and Monday night please check your journey first, it may be that you'll think twice about how you travel.
"I'm sorry if it is more difficult - but my promise is that the work is essential and when it's done the benefits will be worthwhile."
He also said "an army of 14,000 workers" would be working around the clock over the Easter weekend to upgrade lines.
Network Rail has promised to try and prevent a repeat of the rail chaos which occurred at Christmas.
An overrunning engineering project shut the line between Reading and London Paddington at the end of last year.
Julian Burnell, from Network Rail, said  work on the Reading station redevelopment, in its last major stage, was a "very big project, dealing with one of the biggest bottlenecks anywhere in the country".
He added: "I can't say there's absolutely no danger [of an overrun at Easter], but we have done everything in our power to get it finished in good time. There are hundreds of buses waiting if that happens."
Work on the railways this Easter includes:
As a result of the work being undertaken, Virgin is "strongly recommending" that passengers do not travel between Good Friday and Easter Monday.
And speaking of the work being carried out at Watford, Network Rail route managing director Martin Frobisher said: "There is never a good time to carry out this type of work but we have liaised closely with the train operators to plan for it to take place at a quieter time on the railway."
On the roads, Highways England - formerly the Highways Agency - said more than 550 miles of roadworks will be lifted over Easter on England's motorways and major A roads.
According to traffic information company Trafficmaster, the top five busiest stretches of road over Easter are likely to be:
Breakdown company Green Flag said 54,000 callouts were expected over the weekend, with one puncture every minute.  It said the M4 was likely to be one of the worst-congested roads.
Some 16 million cars are expected to take to the roads over Easter.
Gatwick Airport will see some 480,000 passengers between Good Friday and Easter Monday - an increase of about 11% on Easter last year.
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Leeds United have appointed Victor Orta as director of football.

Orta has previously worked as the technical director of Sevilla and spent the last 18 months as the head of recruitment at Middlesbrough.
Leeds chairman Andrea Radrizzani said: "I have been impressed by his knowledge of the game, his extensive scouting network and his desire to help us achieve our objective."
The Elland Road side are managerless after Garry Monk resigned last week.