The bodies of the United States Air Force (USAF) crew killed in a helicopter crash in Norfolk have been removed from the scene.

Capt Christopher Stover, Capt Sean Ruane, Technical Sgt Dale Mathews and Staff Sgt Afton Ponce died in the crash in Cley next the Sea, north Norfolk.
The HH-60G Pave Hawk from the 48th Fighter Wing, based at RAF Lakenheath in Suffolk, came down on Tuesday.
The USAF said no warning or Mayday message was made before the crash.
The Pave Hawk was armed with 600 .50-calibre bullets and a 9mm side-arm with 15 bullets, which were scattered across an area the size of a football pitch.
It was on a low-level night training mission, which Col Kyle Robinson, Commander of 48th Wing described as a routine flight.
"No warning was received about problems with the helicopter," he said.
"Yesterday, we did not fly across the whole 48 Fighter wing, showing our support and condolences for the members of the D6 rescue squadron.
"We will start some limited flight operations today as we continue forward."
He added that it was "still too early to speculate as what caused the crash and make all long-term decisions based on that".
Captains Stover and Ruane were pilots, while Tech Sgt Mathews and SSgt Ponce were acting as special mission aviators.
Col Robinson said they were "flying to a gunnery range in Holbeach [Lincolnshire], and used that frequently for training".
He said the crew, who were members of the 56th rescue squadron, had been in the air force "anywhere from a couple of years to upwards of 16 to 17 years".
"As you would imagine, with most crews, there is a range of experience levels and in general, you have some of the more experienced people [who] will fly with some of the less experienced people and this crew is no different.
"They are all highly qualified in what they did and capable."
Police, air accident, RAF and US investigators have spent the last two days at the scene of the crash.
The USAF, supported by the Ministry of Defence, will lead the continuing investigation into the circumstances of the crash, with Norfolk Police handing over their inquiry.
A 400-metre police cordon is expected to remain in place at the scene until Monday and the public have been asked to stay away.
Norfolk Police Ch Supt Bob Scully said the "dignified and appropriate removal of the bodies" was carried out by USAF officers and staff "under the supervision of Her Majesty's Coroner".
Speaking before the removal, he said it had been a "real sadness that we've not be able to recover the bodies sooner".
"It's a very difficult investigation, on very difficult terrain."
He added that the recovery of the wreckage and munitions and "making good any environmental damage caused by the crash" would take several weeks.
The bodies have been taken to the Norfolk and Norwich University Hospital.
Norfolk Coroner Jacqueline Lake said she would not be carrying out an investigation into the deaths because the airmen had a "relevant association with a visiting force" under the Visiting Forces Act 1952 and Coroners and Justice Act 2009.
Col Robinson added that had been a "tragic, sudden loss".
"The Liberty Wing feels as though it has lost members of its family, and we stand by to support one another and these airmen's families during this difficult time."
Flowers have been left at the gates at RAF Lakenheath and a fundraising page has been set up online to offer financial support to the families.


Doncaster Rovers midfielder Jordan Houghton has been ruled out for the rest of the season with a knee injury.

The 21-year-old was on a season-long loan from Chelsea and had been an ever-present for the side in League Two.
He has now returned to his Premier League parent club for treatment.
Rovers manager Darren Ferguson told the club website: "He has been so important in terms of how we want to play. We're all disappointed for him as he has done so well for us."


Chinese salvagers have fully righted the ship which capsized on the Yangtze River, killing more than 400 people.

The salvage operation began late on Thursday evening in Jianli, Hubei province.
As cranes slowly turned over the stricken ship, relatives gathered to hold a candlelit vigil nearby.
Just 14 of the 456 passengers and crew are known to have survived. Authorities said the chances of finding anyone else alive were slim.
Why did the Eastern Star sink?


Rangers will face Celtic in the semi-final of the Scottish League Cup, while Championship side Greenock Morton will face Aberdeen.

It will be the second Old Firm clash of the season after Celtic thumped their Glasgow rivals 5-1 in their first Premiership meeting on 10 September.
Rangers beat Queen of the South 5-0 on Tuesday, while Celtic beat Alloa 2-0.
Morton, in their first League Cup semi-final for 37 years, will face Aberdeen, who pipped St Johnstone 1-0.
Morton beat fellow Championship side Dundee United 2-1 in the quarter-finals.
The semi-finals will be played on the weekend of 22 and 23 October.
Aberdeen manager Derek McInnes started his playing career at Morton, making over 200 appearances for the Greenock side.
"I am pleased Morton are in the semi-final, that is my club," McInnes told BBC Scotland. "They gave me my start.
"I have huge respect for everyone there, and the work that the chairman and [manager] Jim (Duffy) are doing. I'm delighted they're doing so well.
"It'll be interesting playing against them. Hopefully we will go there in form, hopefully we can keep this killer instinct and winning mentality we have discovered going."


England goalkeeper Joe Hart says he is "surplus to requirements" at Manchester City and does not see himself playing for the Premier League club again.

Hart joined Italian side Torino on a season-long loan in August after being told he was free to leave City by manager Pep Guardiola.
The 29-year-old added that he saw the Spaniard's decision to drop him coming.
"If you're not going to win there is no point in fighting, especially someone as powerful as that," Hart said.
However, Hart believes the decision was "nothing personal" and said he respects Guardiola's honesty.
"He didn't do it to ruin my life, he did it because he thought that was what was right for him to win as a manager," he told the BBC's Premier League Show.
Hart's 33-year-old replacement, Claudio Bravo has been criticised for his performances since his £15.4m arrival from Barcelona in August, with Willy Caballero, 35, preferred in the Premier League and Champions League since 21 January.
Guardiola has said he will not make a decision on Hart's future until the end of the season - but it is expected the keeper will leave the club for good in the summer.
Hart, who has 68 England caps, has been linked with various Premier League and European clubs but said he has had "no communication with anyone" about a transfer after his loan spell at Torino ends in May.
When asked about a return to the Premier League, Hart replied: "I know it really well but I wouldn't say it was top of my wish list.
"Top of my wish list is to play for a club that wants me to be their goalkeeper."
Media playback is not supported on this device
Match of the Day commentator Steve Bower: How difficult was it to discover Pep Guardiola didn't want to make you number one and you would have to go somewhere else?
Joe Hart: I want to say it was really bad but it wasn't because I saw it coming.
SB: From the moment Guardiola walked through the door?
JH: No but you just pick up vibes and it certainly wasn't a surprise to me. It was something that I wanted to change and felt I was more than capable of changing - but to get results he needed to have a team he felt comfortable with and a team he wanted.
I didn't fall into that category and that's no problem. I'd have loved to have stayed and fought and shown what I can do, but I don't have that time. You don't have that time to do it - especially as a goalkeeper. You can't come off the bench for 10 minutes and prove your worth - it's either you're in or you're out.
I'm up for a fight - I'll fight my corner all day - but if you're not going to win then there is no point in fighting, especially someone as powerful as that at Manchester City.
I know it's nothing personal on me, he's not that kind of guy.
SB: Do you respect his honesty?
JH: Yes of course. He did what he had to do, he did what he felt was right. He didn't do it to ruin my life, he did it because he thought that was what was right for him to win as a manager. So I had to look elsewhere and here I am.
SB: What did you say when your agent said Torino were interested?
JH: I said, 'look into it'. I didn't have many options - things happened very late with Manchester City. For a goalkeeper that's difficult, everyone is pretty settled with goalkeepers, it's an early bit of business and there is only one spot.
My name wasn't necessarily out in the transfer market because people probably presumed that I would be at Manchester City - like I did. But I wasn't going to play at Manchester City, that was pretty obvious - I was third, if not fourth choice at the time so I wanted to play football and Torino gave me the opportunity and I just thought, 'I'm going to go for it.'
SB: There will be Manchester City fans thinking, 'Will you ever play for our team again?'
JH: I'd say I'm pretty much surplus to requirements at my parent club at the moment.
SB: Do you see that changing?
JH: Not really. I've got to be realistic. I love that club and I've always said that as long as they wanted me, I would be there.
But I was always cautious when I said that because I'm aware that at the big, big clubs stuff can change quickly, as can opinions and people in charge. Not everyone is going to like you, not everyone is going to want to play you and that's the business side of it, which I've grown into and I'm certainly not going to take personally.
I want to play football, I love to play football so if that opportunity is not going to be given there then I'm going to have to look elsewhere and may have to make somewhere else my home.
SB: Where you at in terms of a transfer at the moment?
JH: It's frustrating to see my name thrown around so much when I'm just trying to get on with what I'm doing for now and then whatever needs to be taken care of will hopefully be taken care of one way or another.
I've still got a parent club that I need to respect and I need to work with. I understand that's the football business now - everyone has got an opinion, a small comment can be used in an article. I don't know where my future lies - I've certainly had no communication with anyone.
The best thing I can do is work hard, be ready to train every day, do my best for Torino, do my best when I represent my country and then hopefully the rest will take care of itself.
SB: How important is it for you to be playing regular football next season to keep your position as England goalkeeper?
JH: [England boss] Gareth Southgate is not the kind of guy to say: 'You need to be doing this or that or you're out.' He's such a positive, interesting person. He came to see me out here, which was good of him, just for an afternoon, just to check in and he wants what's best for the country. The only way I can be a part of that is if I'm playing well, playing regularly and improving.
We've got some really good, strong English keepers at the moment. I'd like to think we're pushing each other and if my levels drop then I'm gone and I understand that. I don't need any threats, I know how the game works as I've been a part of it for a while now.
SB: As a goalkeeper do you have to wait for someone to leave a club for a place to go?
JH: Yes, unfortunately. Especially the top teams because every top team has got at least one top keeper. You need people to move, managers to change. You need something to happen for something to happen. You can't just charge in somewhere.
SB: Would returning to the Premier League be top of your wish list?
JH: I'm open. I love the Premier League, I absolutely love Premier League games. Removing myself a footballer, I watch the Premier League. It's a great league, fantastic football is played in it.
I know it really well but I wouldn't say it was top of my wish list. Top of my wish list is to play for a club that wants me to be their goalkeeper.


The environmental impact of producing a loaf of bread has been analysed in depth from the farm to the shop shelf.

The biggest single factor is the use of fertiliser to grow wheat, which accounts for 43% of greenhouse gas emissions, say experts.
Emissions arise from energy needed to make ammonium nitrate fertiliser and from nitrous oxide released when it is broken down in the soil.
Around 12 million loaves are sold each day in the UK.
Consumers need to be more aware of the environmental costs of their food, say researchers at the University of Sheffield.
There are growing concerns about pollution from plastic packaging around food, as well as wider environmental issues.
Lead researcher Dr Liam Goucher said that in every loaf there is embodied global warming resulting from the fertiliser farmers use to increase their wheat harvest.
"That one key raw material accounts for - in terms of global warming potential - 43% of a loaf of bread," he told BBC News.
"People are well aware of where bread comes from but there's a lack of understanding about perhaps the environmental impact of that bread or the emissions contained by that bread," he added.
The researchers carried out the study to highlight concerns that ammonium nitrate fertiliser is being used "at unsustainable rates".
Up to 60% of crops are grown with the use of fertilisers, made up of chemicals such as methane, carbon dioxide, ammonia and nitrogen.
While synthetic fertilisers can boost the growth of plants - and raise yields - they can also contribute to greenhouse gas emissions.
Prof Peter Horton, a co-researcher on the study, added: "With over 100 million tonnes of fertiliser used globally each year to support agricultural production this is a massive problem, but environmental impact is not costed within the system and so there are currently no real incentives to reduce our reliance on fertiliser."
The research, published in the journal Nature Plants, analysed the complete process behind producing a loaf of bread:
The data found that growing wheat for bread had the biggest influence on producing greenhouse gases, mainly through the use of fertiliser.
This was followed by milling and the bakery stage of the process.
The researchers say there needs to be shared responsibility for the environmental costs of making bread, including fertiliser producers, farmers, millers, bakers, retailers and consumers.


In this series, we have heard how free banking in the UK has been labelled "a misleading con-trick", how customers bewildered by the range of accounts on offer refuse to switch, and how UK consumers get a raw deal should they choose to bank on the internet.

So if tracing the cost of your bank account is as complex as strands of spaghetti, are other countries any better at untangling the mess?
Are their banking charges lower - or at least clearer - and are consumers happier?
The Competition and Markets Authority has announced an extension of its inquiry into the current account market.
The competition watchdog said that more time was needed for the industry and consumer groups to consider its new proposals on softening the impact of overdraft charges on bank customers.
Suggestions include a "monthly maximum charge", an upper limit on combined interest, daily charges and unpaid item fees. This would not be a regulated cap but set by individual banks.
There would be expanded use of grace periods, to allow customers time to top up their account and avoid overdraft fees. Imminent overdraft alerts would be provided as a standard service. Warnings would be sent out by text, email and within apps to tell people that they are about to incur overdraft charges.
Under the proposals, banks would not be able to include arranged overdrafts in the amount of "available funds" which they tell customers they can use. A final decision will be made in August.
The plans were immediately criticised by consumer group Which?.
It said prompts were not enough, and that tougher rules should be set.
"The regulator should use this further extension of their inquiry to bring forward stronger solutions to tackle unfair charges and ensure banks are held to account for how they treat their customers," said Which? executive director, Richard Lloyd.
So, do other countries do banking any better than us Brits?
Along with a cafe serving pastis - and a boulangerie, of course - every small town in France has at least one bank.
But unlike the UK's free-if-in-credit model, in France you will pay to use a bank, whether you are in credit or not.
You will pay a monthly fee to have a current account; you will pay to have a debit or credit card; and you will pay to use a cash-point if it is outside your local region, or if you are using another bank.
Credit Agricole, one of France's largest providers of current accounts, publishes no less than twelve pages of its charges, not counting overdraft rates.
While such charges may look pricey to British eyes, they may actually offer much better value - depending on your spending habits.
"When you look at France, the fees for a missed payment, the fee for sending you a letter, and the overdraft fees are far, far, far lower than in the UK," says Gareth Lodge, an analyst with the US consultancy firm Celent.
But whether you get better value in France varies according to what sort of customer you are.
"If you don't use a card particularly, if you've got very few bills, it probably works out more expensive in France than in the UK," says Lodge.
"If you are using an overdraft a lot more, then that might balance out."
But consumer groups in France are just as frustrated about bank charges as their equivalents in the UK.
The fees may look more transparent, but the campaign group CLVC wants greater accountability. For example, it argues that transaction fees should accurately reflect the actual cost of processing, say, an ATM payment.
CLVC has also calculated that the average cost of the most basic account in France, including a debit card, is around £50 a year.
In a 2016 survey, it said that just 57% of those questioned would recommend their bank to someone else - although overall 72% were happy with their provider.
The number of people switching accounts in the UK continues to fall, much to the disappointment of the government and regulators.
So are they any better at switching abroad?
For its long-running study on bank accounts, the Competition and Markets Authority (CMA) looked at the example of the Netherlands, a market they said was comparable to the UK.
On average, it found that Dutch consumers pay an average of £53 a year for their accounts. Yet, against expectation, that doesn't make them any keener to switch. In a survey local regulators found that 73% of bank customers had never switched at all.
The same could be true in many other countries too.
"I have no proof, but my guess from understanding how the US market works, and how the Dutch and Spanish markets work, is that there's far less switching in other countries," says Gareth Lodge.
"Particularly in the USA and Spain, it's very much your local branch. You stick with it, and you go where your parents went."
However, others suggest that competition is much more lively in France.
"In the French market, there's significantly higher switching," says John Lyons, the retail and commercial banking leader at PricewaterhouseCoopers (PwC).
But that, he says, is because most of the mainstream banks have developed better value internet brands.
"Those digital-only subsidiaries tend not to charge as much as the standard banks. So what you see is a migration from the traditional banks to the internet-only accounts." British banks, take note.
Why consumers get a raw deal from internet banking
If you thought banking sounded expensive in Europe, it can be even pricier in the US.
Most banks charge a monthly fee of up to £10, unless you have a healthy balance sitting in your account.
The Bank of America, for example, charges just under £100 a year, unless you maintain a positive balance of £1,028, or you pay in at least £171 every month.
Some in the US banking industry are therefore amazed by the UK's free-if-in-credit model.
"When Americans hear about the UK market, they think it must be ultra-competitive - which is the opposite of what the CMA thinks," says Lodge.
But most US banks operate at a state level. If you try to cash a cheque "out of state", for example, you're likely to be met with a shake of the head.
And backward though it may seem to Europeans, most Americans are still paid by cheque.
In fact, no less than two-thirds of all the cheques written in the world are written in the USA.
"It's a different model," says John Lyons.
"They have far more regional banks, which are locally-orientated. Generally they are behind."
So which country offers the best value to consumers?
One piece of research into this was done in 2006 by the consultancy Oxera. Not only is it relatively historic, but it was also commissioned by the British Bankers' Association, an organisation always keen to talk up the value provided by UK banks.
But some analysts believe it still provides useful information.
In all five categories - students, young professionals, low-income families, median-income families and pensioners - the UK came in the top three for value as far as current accounts are concerned.
Australia, Canada and Italy provided the worst value.
But experts agree that the UK model is only a good deal in comparison to other countries if you stay in credit.
"If you get free banking, and you utilise it mainly for free transactions, I think you get exceptional value," says John Lyons.
"If you're part of the segment that relies on other products that banks use to cross-subsidise those costs, you could argue you're not getting good value."
As long as you don't think "free" banking is actually free, the deal for prudent consumers in the UK may not be quite so bad, after all.


The Royal College of Nursing has held an emergency board meeting later in response to a pay award which unions have described as an insult.

They are now to ballot members on taking industrial action short of a strike.
Health Minister Simon Hamilton said the majority of health care workers, including nurses, would receive a one-off payment.
The 1% increase would equate to about £300 for most.
The RCN has said the increase should be added to salaries as has been the case in other parts of the UK.
It said nurses in Northern Ireland are worse off than their counterparts in England and Scotland.
However, the health minister has said it is a fair deal.
Following Monday's meeting, Janice Smyth, director of the Royal College of Nursing in Northern Ireland, said: "Board members considered the imposed pay award, the manner in which the Minister made this announcement and the tone of the announcement.
"They have considered the views and opinions expressed by members who contacted the RCN over the weekend, and taken account of the detail of the Minister's announcement."
She added: "Today, members of the RCN Northern Ireland board voted unanimously to consult RCN council seeking authorisation to ballot RCN members in Northern Ireland in relation to the imposed pay award announced by the minister and taking industrial action short of strike action."
For the health minister this is about the best allocation of scarce resources, for nursing unions it's about fairness and recognition of hard working health care staff.
The pay settlement announced by the minister last Friday afternoon falls far short of what the unions wanted.
It sets out a 1% rise for the 60% of health care staff who are at the top of their pay band.
That rise is non-consolidated, which means it is effectively a one-off bonus which won't necessarily be added into next year's pay.
The 1% payment will equate to around £300 for most, with a maximum of £985.
The other 40% of staff who aren't at the top of their pay band, will get their normal annual incremental rise.
This will on average be 3.7% rise which will equate to a minimum of £1,588.
The unions want the 1% rise to be consolidated, meaning it would increase annual salaries and wouldn't be a one off payment.  This has been the case in Scotland.
However, Mr Hamilton said his officials had sought to engage with union leaders on a 2015-16 settlement since 4 January 2015.
"I would have preferred an agreed settlement but when I met recently with trade union representatives they unfortunately remained unwilling to move beyond seeking to reopen last year's settlement despite it having being paid into people's accounts many months ago and with their union colleagues across the water having moved ahead and focused on 2015-16," he said.
"The pay demands made by the trade unions would cost my department's budget close to £40m and are simply unaffordable in current circumstances."
The RCN had already decided to ballot members on industrial action short of a strike later this month.


Senior councillors from across Scotland are due to meet to discuss the government's education policy.

The Scottish government has said raising attainment is a key priority.
Education conveners from 28 local authorities, which run schools,  will debate the issue at the meeting hosted by council umbrella body Cosla.
They are expected to focus on how money resulting from council tax changes will be spent.
From next April, people in the most expensive homes will pay more.
This is because the multiples between the different property bands will change - those in the most expensive bands will pay more, irrespective of whether a council decides to put up the basic level of the council tax.
The government wants the Â£100m this is expected to raise handed to headteachers to spend directly on their schools - specifically on schemes to help raise  attainment and close the gap between how well youngsters from relatively rich and poor backgrounds do.
Some in local government want to ensure councils retain the freedom to decide for themselves just how much they need to spend on education and would want to automatically retain all the extra money from the council tax changes.
Critics also fear that the government could, in effect, decide to put the money into a national pot to redistribute back to councils or individual schools. Some areas would receive more or less than they would have raised locally.
Some councils would react furiously to any attempt by central government to take the money from them or dictate just how it would be spent.
No decisions have been taken yet by the Scottish government although it has made it clear it wants all the extra money spent on education.
The issue is likely to come up during the talks between councillors and the government over next year's funding package.
On Monday, Education Secretary John Swinney told BBC Scotland there were "detailed arrangements to be discussed with local government" on future changes.
He explained: "We made clear in our election manifesto that we would change some of the aspects of council collection, to expand the bands and increase some of the thresholds and that would generate Â£100m which we would invest in the attainment fund."


The discovery of claw marks in a bone-filled cave in Australia suggests an extinct, "anatomically bizarre" predator was able to climb trees and rocks, meaning it would have been a threat to humans, writes Myles Gough.

Australia's extinct marsupial lion, Thylacoleo carnifex, was the continent's top predator at the time of human arrival 50,000 years ago.
Weighing more than 100kg, the animal had sharp claws and a powerful jaw, and shearing teeth that could rip through the flesh of its prey, which included giant kangaroos, rhinoceros-sized herbivores known as diprotodon, and possibly humans.
But while experts agreed on the marsupial lion's fearsomeness, whether or not they could climb rocks and trees has been a source of contention.
Some speculated that the lions' anatomy would lend itself to climbing, while others argued they would have been too heavy to clamber up to high places.
Now palaeontologists at Flinders University say they have found the answer in a cave in Western Australia where marsupial lions left thousands of scratch marks.
The scratch marks, mostly made by juveniles and clustered on a near-vertical rock surface leading to a now-sealed exit, suggest two things about the lions: they were skilled climbers, and they reared their young inside caves.
"[Our findings indicate] the [marsupial] lions were running up and down these rock piles to get out of the cave, and they weren't using the lower-gradient, longer route," says associate professor Gavin Prideaux, who supervised the research.
"We can be confident now and say that they could climb.
"And if they could climb really well in the dark, underground, there's no reason they couldn't climb trees.
"They would have been a very significant threat to people when they first arrived in Australia.
"What we're dying for are different lines of evidence that shed light on the behaviour or ecology of these animals, and that's what we've been presented with in the form of these claw marks."
The team's findings, which reinforce some contentious ideas about the behaviour of these "highly adapted" and "anatomically bizarre" predators, have been published in Nature's open-access journal Scientific Reports.
The claw markings were found inside the Tight Entrance cave near the Margaret River.
In the mid-90s, bones inside the cave were identified as belonging to extinct megafauna, dating from 30,000 to 150,000 years old, says Prof Prideaux.
Between 1996 and 2008, he went on numerous expeditions to the cave to collect fossils, and during that work discovered the scratch marks.
"We had the feeling that they were probably Thylacoleo scratch marks, but we had to test it," he says.
Prof Prideaux and his honours student, lead author Samuel Arman, established a list of seven species of animal that could have been responsible.
It included the extinct marsupial lion, as well as Tasmanian tigers and Tasmanian devils, which used to live on the mainland, wallabies, koalas, possums and wombats.
Mr Arman left scratch pads inside zoos and wildlife parks, and collected tree bark to get sample claw markings from the living animals, which he compared to those inside the cave.
This helped the researchers narrow their list to two key suspects: marsupial lions and Tasmanian devils. But they needed another clue.
"We went through the more than 10,000 bones we collected from the cave to look for evidence for bite marks or little chewed-up bones [which are] absolute hallmarks of devil dens," says Prof Prideaux.
"We found zero of that."
"This is more consistent with what we've inferred about the behaviour of Thylacoleo from its dental morphology, and that is, it was primarily a meat eater and not a bone cruncher."
Mr Arman also reconstructed a skeletal hand of the marsupial lion and made mock scratches on modelling clay that "perfectly matched" the large ones found in the cave.
The animals, which became extinct around 46,000 years ago, lived all across the continent. Prof Prideaux suspects similar claw markings exist in caves elsewhere, but have yet to be discovered.
Dr Judith Field, an expert in megafaunal extinctions from the University of New South Wales, says "the methods used to determine the size of the animal making the marks appear well conceived and well executed".
"It is highly likely these marks were made by Thylacoleo," she told the BBC. "They are probably the only animal with claws large enough to effect these scratch marks."
Still, Dr Field expressed some reservations about the study: "Most of the conclusions are speculation," she said. "Great discovery, and a neat story, but these assertions about their behaviour have yet to be substantiated by empirical data."


Oscar-nominated actor Stanley Tucci has admitted he does not enjoy working on CGI and 3D films, despite starring in new 3D movie Jack The Giant Slayer.

The star, who plays villain Lord Roderick in the film, described the process as "humiliating".
"I can't stand 3D, I really can't. I'm happy to go watch it but I don't work shooting in 3D. It's not fun," he said.
Tucci was nominated for an Oscar in 2009 for his role in The Lovely Bones and starred in The Hunger Games.
Brian Singer's adventure, based on the fairytale Jack and the Beanstalk, also stars Nicholas Hoult and Ewan McGregor.
Tucci said: "Nobody will tell you it's so fun shooting in 3D. We were all dressed in stupid outfits.
"It was pretty funny sitting around in chairs, everybody with little caps on, tight spandex things with little balls all over you. I'm not kidding.  It's so humiliating!"
He added: "We had a lot of difficulty with the cameras, they broke down a lot and the crew was cursing them.
"Ultimately it looks amazing and you have to be patient, but when you're sitting around for 13 hours a day in soaking wet leather doublets, and you maybe get two shots off a day, it's kind of frustrating."
The actor, who won an Emmy Award for his performance in HBO TV film Winchell and also starred in The Devil Wears Prada, said the new technology made it less interesting for actors.
"You end up doing a lot of stuff in front of green screen, that's not really very exciting for an actor," he said. "We're probably going to be replaced by digital-something soon.
"I'm hoping either I'll have enough money I won't have to worry about it at that point, or I'll be dead... They need voices for animation, but soon they'll figure that out too.
"I'll be honest, an independent film, you do it because you love it, but I think motion capture movies are the ones where you have to be paid a lot of money.
Released in the US on 1 March, Jack The Giant Slayer underperformed at the box office, taking $28m (Â£18.6m) in its opening weekend. The film reportedly cost $189m (Â£125.5m) to make.
It will be released in UK cinemas on 22 March.


David Cameron says he will set out his EU reform demands within weeks and pledged to "quicken the pace" of talks.

His proposals will be published in a letter to European Council president Donald Tusk in early November.
Earlier EU Parliament president Martin Schulz called for "clarity" while German Chancellor Angela Merkel said Britain needed to "clarify the substance" of what it wanted.
Mr Cameron wants to reform the EU ahead of the UK's in-out referendum.
Arriving for his talks with Mr Schulz, the PM, who also met European Commission president Jean-Claude Juncker over lunch, said the British renegotiation was "going well" and pointed to the progress of the UK legislation paving the way for the referendum.
"The pace will now quicken, and I'll be again setting out the four vital areas where we need change, laying down what those changes will be at the start of November," he said.
"So we quicken the pace and quicken those negotiations in the run-up to the December Council."
Q&A: UK's planned EU referendum
The December meeting of the European Council will be a chance for Mr Cameron's demands to be considered by his EU counterparts.
On Twitter, Mr Tusk welcomed Mr Cameron's plan to write to him with the UK's demands in early November, saying: "Then real negotiations can start".
Downing Street confirmed the letter would be made public when it is sent in early November.
In the meantime, talks have been taking place between UK and EU negotiating teams, but Mr Juncker said on Wednesday that "huge progress" was not being made and reminded the UK that "it takes two to tango".
BBC Europe correspondent Chris Morris said those involved in the "technical talks" accepted they had "got as far as they can" and that the negotiations needed to "move onto the political level".
The referendum has been promised by the end of 2017, but could be held sooner.
Mr Cameron has not yet set out his demands in detail, but is thought to want exemption from an "ever-closer union", safeguards for non-eurozone countries and curbs on migrants' welfare entitlement.
Speaking at a press briefing with Mr Juncker shortly before Mr Cameron's arrival, Mr Schulz said: "Both of us have made it quite clear that both the Commission and the European Parliament at all stages are willing to engage in constructive co-operation."
He said he hoped for "steps forward", adding: "Above all, we need clarity on what we are going to be discussing over the next few months."
Ms Merkel said it was up to the UK to "clarify the substance of what it is envisaging" in the coming weeks.
She said Germany would work constructively with the British government.
She added: "But it also goes without saying that there are things that are non-negotiable.
"That there are achievements of European integration that cannot be haggled over, for example the principle of free movement and the principle of non-discrimination."


UK economic growth was "robust" in late 2016, but economists have warned of worrying signs as the savings ratio fell to a record low.

The Office for National Statistics (ONS) confirmed the UK economy grew by 0.7% in the final three months of 2016.
Economists said that was driven by a rise in consumer spending, partly funded by households dipping deeper into savings and running up debt.
The savings ratio fell to its lowest since the early 1960s, the ONS said.
It said the ratio - which measures the outgoings and incomings that affect households - partly fell in the final quarter of last year because of changes in insurance and pension values.
But it was also part of a wider trend, which has seen the ratio fall since mid-2015 as consumer spending outstripped growth in disposable incomes.
John Hawksworth, chief economist at PwC, said: "On the surface, today's national accounts data reconfirmed the earlier picture that the UK economy remained relatively robust in the second half of 2016 following the Brexit vote.
"Beneath the surface though, some more worrying signs are evident."
Among them is that household net borrowing in the fourth quarter rose to over Â£11bn, the highest quarterly level in nearly 30 years, he said.
"This pushed the household savings ratio in [the fourth quarter of] 2016 down to its lowest level since comparable records began in 1963," he added.
The Bank of England has predicted that weaker incomes will result in a "significant fall" in the saving ratio over the next three years.
The UK's economy last year defied forecasts that it would slow sharply after the vote in June to take the country out of the European Union.
However, inflation has gathered pace in recent months, driven in part by the fall in the value of sterling since the Brexit vote.
With prices rising and wage growth slowing, 2017 was "likely to be a very tough year for the consumer", said Martin Beck, senior economic advisor to the EY Item Club.
He added that monthly figures for the services sector indicated that output fell 0.1% in January.
The British economy continued to grow strongly at the end of last year boosted by the dominant services sector and increasing exports.
That meant that growth for the whole year was a respectable 1.8%.
The two key factors were the fall in value of the pound which has helped British exporters to boost exports by 4.6% and by strong consumer spending that has kept the services sector of the economy performing well.
Household spending rose by 0.7% in the last three months of 2016 alone. But there are signs that may not continue for long; inflation is now rising at almost the same rate as wages and that is likely to squeeze spending power, while households have few savings to fall back on.
The savings ratio at 3.3% is already at its lowest level since records began in 1963.
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Just how far is Russia prepared to go to back the Syrian regime of President Bashar al-Assad?

Recent sightings of brand new Russian armoured vehicles in Syria, of types never previously supplied to its ally, suggest that with the Assad regime suffering serious reverses, Moscow is intent on redressing the military balance.
On 20 August, a heavily-laden Alligator class landing ship of the Russian Navy, the Nikolay Filchenkov, was seen passing southwards through the Bosphorus.
On board, according to experts who have analysed the images, were trucks and armoured vehicles.
The ship was believed to be on its way to Syria.
Subsequently, the Syrian army has released video material that shows seemingly brand new BTR-82A infantry combat vehicles in action or on exercises - a variant of the vehicle that has never before been supplied to the Syrian military.
The vehicles appear to be in a Russian paint scheme and thus may have been taken straight from Russian army stocks.
Separate images have emerged of Russian Tigre military utility vehicles; again a type that has not been exported to Syria before.
Caution must always be used when analysing this kind of material.
But Joseph Dempsey, an expert at the International Institute for Strategic Studies in London, says that the images "if authentic, provide strong evidence of the BTR-82A and Tigr being in Syria".
The delivery of these weapons raises all sorts of questions.
Why should new types not previously operated by the Syrians be supplied by Russia rather than older vehicles - like the BMP-tracked combat vehicle with which the Syrian army is familiar?
Syria did receive a small number of the related BTR-80 armoured personnel carrier in late 2013/early 2014 but the BTR-82A has a more modern and very different turret and weapons station.
Is this the first delivery of many? And who actually is operating the system?
Russia is one of the Syrian president's few foreign allies. It has long been a major arms supplier to Syria and, in the current crisis, it has given the Syrian regime important diplomatic support.
Russia was instrumental in helping to negotiate the deal in 2013 under which the Assad regime gave up its chemical weapons.
Russia has long maintained a small naval base on the Syrian coast at Tartus. It represents a toehold for Russian influence in the region that peaked during the 1970s at the height of the Cold War.
However, the Syrian crisis has alarmed Moscow.
It is every bit as concerned by the rise of the murderous religious radicals of the so-called Islamic State (IS) movement as is the West.
Russia did not respond to the upheavals of the "Arab Spring" with the enthusiasm of many Western governments.
And in retrospect, given that hopes for a democratic surge through the region have collapsed, Russia's hard-headed pragmatism looks to be a little more realistic than much of the West's "aspirational" diplomacy.
The Syria crisis also provides Russia with an opportunity. Its ties to the Assad regime make it a key player.
Russian Foreign Minister Sergei Lavrov has forcefully reiterated Russia's position that the departure of Mr Assad cannot be a condition for any peace deal.
Such demands, he says, are "totally unrealistic and counterproductive".
Russia insists that it is working to create what it calls a "broad anti-terrorist front" to counter IS.
But the crucial thing for Russia is that the Assad regime must survive, whatever Mr Assad's personal fate in the longer term.
Much of the attention over recent weeks has focused on Russia's diplomatic efforts regarding Syria; its talks with senior Saudi and Iranian officials, for example.
But, in the meantime, things have not been going well for Mr Assad on the ground, with his opponents pressing ever closer to the Alawite heartland - the coastal basin to the east of the Mediterranean, inland from Latakia and Tartus.
Amidst the uncertainty, a host of rumours are flying round of a much greater Russian role. Russia has denied that it recently delivered advanced warplanes to Syria.
Some Israeli analysts, for example, believe that Russia is preparing to use its own aircraft against IS and might even be willing to play a greater role on the ground if the Assad regime's fortunes do not change.
This for now may be little more than speculation.
The Russians themselves have denied that any aircraft have been deployed to Syria to prepare for strikes against IS.
One expert, Ruslan Pukhov, a spokesman for Russia's arms industry, believes that what the Syrian forces require right now is "ammunition, light weapons, communications and UAVs [drones]".
But the signal from the Nikolay Filchenkov may be that if needed, Russia is willing to provide a good deal more.


Italy's highest court has upheld a prison sentence given to former PM Silvio Berlusconi for tax evasion.

The court also ordered a further judicial review on whether he should be banned from holding public office.
In an emotional video statement, Berlusconi denounced the decision as "based on nothing, and which deprives me of my freedom and political rights".
The sentence cannot be appealed against further but Berlusconi, 76, is unlikely to go to jail because of his age.
The ruling by the Court of Cassation in Rome came after a three-day hearing. Berlusconi was not in court.
The former prime minister was sentenced to four years in prison at the conclusion of the trial last October, though this was automatically reduced to a year under a 2006 pardon law.
Berlusconi is likely to serve house arrest or carry out community service.
His lawyers described Thursday's ruling as "unjust".
By Alan Johnston BBC News, Rome
The courtroom dramas of Silvio Berlusconi are part of the backdrop to Italian life. The nation has watched around two dozen trials unfold over nearly 20 years.
But until now they have never seen Berlusconi definitively convicted. And there can be no appeal.
This damning judgement will forever be part of his record - and he will surely see this as one of the darkest moments in his extraordinary political career.
But it could have been even worse: the judges did not uphold the order that would have barred Berlusconi from public office. That will be re-examined by a lower court.
So Berlusconi is certainly down, but not entirely out. He has been diminished and humiliated, but even now it might be a mistake to bet against him.
They had been hoping to overturn his conviction in a case involving television rights bought by his company Mediaset.
It is the billionaire businessman's first definitive conviction after decades of criminal prosecutions.
In his video message after the court's decision he said: "I never devised any system of fiscal fraud. No false invoice exists in the history of Mediaset."
Berlusconi said he was the victim of "an incredible series of accusations and trials that had nothing to do with reality".
He described the more than 50 court cases he has faced as "genuine judicial harassment that is unmatched in the civilised world".
The review of the lower court's five-year ban on holding public office means Berlusconi can remain as a senator and as leader of his centre-right People of Freedom Party (PDL) for now.
The BBC's Alan Johnston in Rome says the former prime minister will be relieved that judges ordered a review of the political ban.
Berlusconi's political grouping forms part of Italy's coalition government. Prime Minister Enrico Letta needs both the PDL and his own centre-left Democratic Party to govern.
In a statement after the court ruling, Mr Letta urged "a climate of serenity" for the good of the country.
President Giorgio Napolitano also urged the country to stay calm.
"The country needs to rediscover serenity and cohesion on vitally important institutional matters that have for too long seen it divided and unable to enact reforms," he said.
A former minister and ally of Berlusconi, Nitto Palma, told Reuters on leaving a PDL meeting that there was a lot of bitterness about the verdict.
However, the sentence would not affect the Letta government, he said.
Berlusconi's legal team said there were "solid reasons" why their client should have been acquitted, and they would "evaluate and pursue any useful initiative, also in Europe, to make sure that this unjust sentence is radically reformed".
Anti-establishment politician Beppe Grillo welcomed the court ruling, comparing the sentence to the fall of the Berlin Wall.
In a statement on his blog, Mr Grillo said Berlusconi had "polluted, corrupted and paralysed Italian politics for 21 years".
The original ruling last October found that Berlusconi's Mediaset media empire had inflated the price it had paid for film distribution rights to avoid paying taxes.
He was labelled the "author of a whole system of tax fraud".
The three-time prime minister has faced a string of trials since leaving office in November 2011.
Appeals are pending in other cases in which he was convicted of having paid for sex with an under-age prostitute, and arranging for a police wiretap to be leaked and published in a newspaper.
Two other cases of alleged tax evasion, one of them involving British lawyer David Mills, expired under the statute of limitations.


A chicken-sized dinosaur fossil found in China may have overturned a long-held theory about the origin of birds.

For 150 years, a species called Archaeopteryx has been regarded as the first true bird, representing a major evolutionary step away from dinosaurs.
But the new fossil suggests this creature was just another feathery dinosaur and not the significant link that palaeontologists had believed.
The discovery of Xiaotingia, as it is known, is reported in Nature magazine.
The authors of the report argue that three other species named in the past decade might now be serious contenders for the title of "the oldest bird".
Archaeopteryx has a hallowed place in science, long hailed as not just the first bird but as one of the clearest examples of evolution in action.
Discovered in Bavaria in 1861 just two years after the publication of Darwin's Origin of Species, the fossil seemed to blend attributes of both reptiles and birds and was quickly accepted as the "original bird".
But in recent years, doubts have arisen as older fossils with similar bird-like features such as feathers and wishbones and three fingered hands were discovered.
Now, renowned Chinese palaeontologist Professor Xu Xing believes his new discovery has finally knocked Archaeopteryx off its perch.
His team has detailed the discovery of a similar species, Xiaotingia, which dates back 155 million years to the Jurassic Period.
By carefully analysing and comparing the bony bumps and grooves of this new chicken-sized fossil, Prof Xu now believe that both Archaeopteryx and Xiaotingia are in fact feathery dinosaurs and not birds at all.
"There are many, many features that suggest that Xiaotingia and Archaeopteryx are a type of dinosaur called Deinonychosaurs rather than birds. For example, both have a large hole in front of the eye; this big hole is only seen in these species and is not present in any other birds.
Several species discovered in the past decade could now become contenders for the title of most basal fossil bird.
Epidexipteryx - a very small feathered dinosaur discovered in China and first reported in 2008 (above). It had four long tail feathers but there is little evidence that it could fly.
Jeholornis - this creature lived 120 million years ago in the Cretaceous. It was a relatively large bird, about the size of a turkey. First discovered in China, and reported in 2002.
Sapeornis - lived 110 to 120 million years ago. Another small primitive bird about 33 centimetres in length. It was discovered in China and was first reported in 2002.
"Archaeopteryx and Xiaotingia are very, very similar to other Deinonychosaurs in having a quite interesting feature - the whole group is categorised by a highly specialised second pedo-digit which is highly extensible, and both Archaeopteryx and Xiaotingia show initial development of this feature."
The origins of the new fossil are a little murky having originally been purchased from a dealer. Prof Xu first saw the specimen at the Shandong Tianyu Museum. He knew right away it was special
"When I visited the museum which houses more than 1,000 feathery dinosaur skeletons, I saw this specimen and immediately recognised that it was something new, very interesting; but I did not expect it would have such a big impact on the origin of birds."
Other scientists agree that the discovery could fundamentally change our understanding of birds. Prof Lawrence Witmer from Ohio University has written a commentary on the finding.
"Since Archaeopteryx was found 150 years ago, it has been the most primitive bird and consequently every theory about the beginnings of birds - how they evolved flight, what their diet was like - were viewed through the lens of Archaeopteryx.
"So, if we don't view birds through this we might have a different set of hypotheses."
There is a great deal of confusion in the field says Prof Witmer as scientists try to understand where dinosaurs end and where birds begin.
"It's kind of a nightmare for those of us trying to understand it. When we go back into the late Jurassic, 150-160 million years ago, all the primitive members of these different species are all very similar.
"So, on the one hand, it's really frustrating trying to tease apart the threads of this evolutionary knot, but it's really a very exciting thing to be working on and taking apart this evolutionary origin."
Such are the similarities between these transition species of reptiles and birds that other scientists believe that the new finding certainly will not mean the end of the argument.
Prof Mike Benton from the University of Bristol, UK, agrees that the new fossil is about the closest relative to Archaeopteryx that has yet been found. But he argues that it is far from certain that the new finding dethrones its claim to be the first bird.
"Professor Xu and his colleagues show that the evolutionary pattern varies according to their different analyses.
"Some show Archaeopteryx as the basal bird; others show it hopped sideways into the Deinonychosaurs.
"New fossils like Xiaotingia can make it harder to be 100% sure of the exact pattern of relationships."
According to Prof Witmer, little is certain in trying to determine the earliest bird and new findings can rapidly change perspectives.
"The reality is, that next fossil find could kick Archaeopteryx right back into birds. That's the thing that's really exciting about all of this."


A number of caravans have been damaged by a large tyre fire in Flintshire.

Three fire engines were sent to Spring Street, in Connah's Quay, to tackle the blaze in the early hours.
The cause of the fire, which spread to the nearby caravans, is not yet known, North Wales Fire and Rescue Service said.
No-one was injured.


A 55-year-old man has died following a two-vehicle crash on the A1 near Dromore, County Down.

It happened at about 07:15 GMT close to Halfway Road.
A woman was taken to hospital following the collision. Police said her injuries were not believed to be life-threatening.
The road was closed in both directions for much of the day, but has since reopened.


Probation officers are supervising up to 80 offenders at any one time - leaving the public at greater risk, a watchdog has warned.

HM chief inspector of probation, Dame Glenys Stacey, highlighted large caseloads in a report on Staffordshire.
The Reducing Reoffending Partnership, which owns the area's Community Rehabilitation Company (CRC), said probation experts "work hard".
The Ministry of Justice said a "robust action plan" was in place.
Read more news for Stoke and Staffordshire
In 2014 probation services in England and Wales were divided into a new National Probation Service (NPS) and 21 privately-owned rehabilitation companies.
High-risk individuals are managed by the NPS while CRCs are responsible for other offenders.
Dame Glenys said the area's NPS and the Staffordshire and West Midlands CRC needed to improve the quality of their work.
The report said the CRC's programmes, including Drink Impaired Drivers Programme and one to address domestic abuse, "are staffed by a well-resourced and experienced team".
The CRC also commissioned specific services for women service users, the report stated.
But Dame Glenys said too much of the CRC's "bread and butter work to protect the public was wanting".
The report said assessments of the risk of harm were done "to an acceptable standard", but they "were not followed through sufficiently well".
It also said some officers were responsible for up to 80 cases.
Dame Glenys said the work of the NPS in the region was of "sufficient quality", but there were "notable weaknesses" in places.
Reducing Reoffending Partnership chief executive, Catherine Holland, said: "Our team of probation experts work hard to keep the people of Staffordshire and Stoke safe by reducing reoffending.
She added it would use the report's findings to "further strengthen our work".
A Ministry of Justice spokeswoman said providers were "rigorously" held to account for their performance, adding a "robust action plan" for the area was in place to address the inspectorate's concerns.
The plan includes developing a new tool to assess offenders' risk.


A US project to create a printable gun has been derailed after the company supplying the 3D printer withdrew it.

In a letter published on the Wiki Weapon website, Stratasys said that it did not allow its printers "to be used for illegal purposes".
Defense Distributed, the group behind the project, had planned to share 3D weapon blueprints online.
Currently it is legal in the US to manufacture a gun at home without a licence.
Defense Distributed raised $20,000 (Â£12,400) online to get the Wiki Weapon project started.
It planned to develop a fully printable 3D gun, initially with no moving parts.
"This project could very well change the way we think about gun control and consumption," it said on its site.
"How do governments behave if they must one day operate on the assumption that any and every citizen has near instant access to a firearm through the internet?"
But the project hit a snag when the firm supplying the 3D printer got wind of what they were planning.
In a letter to Defense Distributed founder Cody Wilson, Stratasys said that it had taken the decision to withdraw the printer "based on your lack of a [firearms] licence and your public statements regarding your intentions in using our printer".
"It is the policy of Stratasys not to knowingly allow its printers to be used for illegal purposes. Therefore please be advised that your lease of the Stratasys uPrint SE is cancelled at this time."
The firm collected the machine several days later.
Government laws on the manufacture of guns will need quick revision to catch up with the age of 3D printing, thinks Marc Goodman, head of the Future Crimes Institute.
"This appears to be a grey area under US law and the laws of other countries. The question is: how do you control technology that can do illegal things?" he said.
"In this case, this was being done very overtly and trying to prove a point. I am far more concerned about the people who aren't publicising it."
Mr Goodman predicts that 3D printing could be the next battleground in the fight against organised crime and terrorism. And it won't just be weapons that will be printed online.
"It will be the next frontier in IP [Intellectual Property] theft when you are able to manufacture a Rolex watch, Gucci handbags, Nike sneakers," he said.


An "abusive passenger" has caused widespread disruption to rail services in the Glasgow area, ScotRail has said.

The passenger was on board the 17:00 Anderston to Carstairs train, but the service was terminated at Rutherglen because of the incident.
ScotRail said all trains through Rutherglen could be delayed or cancelled.
British Transport Police said it was called to the station at about 17:30 over reports of an "abusive male".
A spokesman for the force said the man had reportedly been aggressive to rail staff.
Services to Dalmuir, Milngavie, Cumbernauld, Motherwell, Larkhall, Anderston, Carstairs, Glasgow Central, Lanark and Edinburgh via Shotts could be affected by the incident.
A ScotRail Alliance spokesman said: "We do not tolerate abusive or anti-social behaviour of any kind on our trains. We will work with the British Transport Police to assist them in bringing the individual involved to justice.
"Customers delayed by 30 minutes or more as a result of this incident are reminded to keep hold of their tickets to claim compensation through our Delay Repay Guarantee."


Two match officials who appeared to be drunk during a top-flight game have been banned by the Czech Football Association (FACR).

It occurred during Slavia Prague's win at relegation-threatened FK Pribram.
The FACR said fourth official Marek Pilny and additional assistant referee Jiri Jech would lose their licences and face disciplinary action.
A statement said Pilny was "visibly drunk", adding that Jech had allegedly "urinated during the game".
Pilny's actions were caught on video and posted on YouTube.
The statement added that Pilny "struggled for balance" and "ran with the linesman copying his movements".
FACR head Miroslav Pelta said "they were not tipsy, they were drunk" and "they don't exist for us any more".
Pelta also said the game's referee and two linesmen would be suspended until the end of the season because they failed to prevent the situation.


India's iconic Taj Mahal has been threatened in recent weeks by insect poo - environmentalists say that bugs from the polluted Yamuna river nearby are invading the monument, leaving greenish-black patches of waste on its pristine white marble walls.

Over the years, the 17th Century monument has been threatened by pollution, unabashed construction, a crematorium and even bombs.
The BBC's Geeta Pandey in Delhi reports on five threats - past and present - to India's "monument of love".
An invasion of the insect called Chironomus Calligraphus (Geoldichironomus) is turning the Taj Mahal green, says environmental activist DK Joshi.
Mr Joshi has filed a petition in the National Green Tribunal - a special tribunal set up by the government to deal with environmental disputes - saying that the "explosive breeding" of the pests in the polluted Yamuna river is marring the beauty of the monument.
"Fifty-two drains are pouring waste directly into the river and just behind the monument, Yamuna has become so stagnant that fish that earlier kept insect populations in check are dying. This allows pests to proliferate in the river," Mr Joshi told the BBC by phone from the northern city of Agra where the Taj is located.
The stains the bugs leave on the marble are washable and workers from the Archaeological Survey of India (ASI) have been trying to scrub the walls clean, but Mr Joshi says frequent scrubbing can take the sheen off the marble.
He says the problem has a simple solution - just clean up the Yamuna.
On Monday, Uttar Pradesh Chief Minister Akhilesh Yadav ordered officials to "trace the factors behind the problem and find a solution".
Built by Mughal emperor Shah Jahan as a mausoleum for his beloved wife Mumtaz Mahal, who died in childbirth, Taj Mahal is often described as one of the wonders of the world.
It is also India's biggest tourist attraction, visited by heads of states, celebrities and millions of Indian and foreign tourists every year.
But pollution from the industries in Agra and a nearby oil refinery have seen the white marble yellowing over the years.
To restore the monument's beauty, the ASI has been applying "mud packs" on its walls to draw out the pollutants.
Manoj Bhatnagar of the ASI's chemical department told the BBC that the mud-pack is based on a traditional recipe used by Indian women from ancient times to restore a natural glow to their faces.
"A layer of fullers earth - a type of lime-rich clay - mixed with water is applied over the walls and left on for 24 hours or more to dry," he said.
"Once it dries, the mud is removed and the surface is washed with distilled water to remove impurities."
The marble mausoleum had been given this treatment several times in the past: in 1994, 2001, 2008 and 2014.
Mr Bhatnagar said the next round of beauty treatment will begin once the weather cools a bit - the heat wave currently blowing across India will dry out the mud-pack too quickly and render it ineffective.
In November 2002, the government of the Uttar Pradesh state began work on a shopping complex near the Taj Mahal.
The state government, led by then chief minister Mayawati, said the mall was being constructed to relocate shops that had been removed from the Taj Mahal under a Supreme Court order.
The authorities said that once the mall opened, tourists would be able to visit the Taj without having to go through the crowded and polluted streets.
However, the project prompted howls of protest from environmentalists who said the project violated environment protection laws and placed the monument at risk.
The proposal was eventually abandoned.
Last year, India's Supreme Court ordered a wood-burning crematorium near the Taj Mahal to be moved to protect the monument from the smoke and ash blown over from funeral pyres.
The court said the authorities could either move the 200-year-old crematorium or build an electric powered one to reduce pollution to the monument.
The state government agreed, but faced protests from some Hindu groups. So far, the crematorium still has not been moved.
Security at the Taj Mahal was tightened last year after reports that al-Qaeda had threatened to attack the monument.
This was not the first time the Taj had been on the radar of militant groups - in January 2001, security was stepped up after reports that Pakistan-based militant group Laskhar-e-Taiba was threatening to blow up the monument.
Police said they were investigating an e-mail from the group threatening to attack the Taj, but a spokesman for LeT denied the allegation, saying it was Indian propaganda to discredit them.


The stakes have been raised in the bidding war for the gaming firm Bwin.party.

GVC Holdings has raised its takeover bid to about £1bn, topping an offer from 888 Holdings.
888 bid £898m for the firm earlier this month, an offer Bwin accepted.
GVC said it was "working on finalising" its bid, which Bwin said would be considered by its board, although it cautioned "there can be no certainty that an offer will be made by GVC".
GVC's offer is worth 122.5 pence per share, which will be made up of 25 pence in cash and 1 new GVC share.
The 888 deal valued Bwin shares at 104.09p each. This latest move comes less than six months after 888 rejected a takeover bid from William Hill, which valued it at about £750m.
Online gambling companies are merging to try and reduce operating costs as they are exposed to stricter regulation.
"This is a real statement of intent from GVC. The proposed premium over the accepted offer by 888 is such that the bwin.party board will probably have no choice but to reconsider its acceptance of the 888 offer," analysts at Davy Research said.
"We would be surprised if 888 does not come back with a counter-offer of its own."


A hoard of coins discovered in Jersey one year ago is the "largest in the Celtic world", according to an expert on the island.

Jersey Heritage Trust Conservator Neil Maher has spent the past year creating a model of the one tonne mound of silver and copper coins, gold pieces and mud.
He said: "This is the world's biggest Celtic coin hoard ever, this was a significant part of a tribe's wealth.
"It is also one of the world's biggest coin hoards and certainly the biggest coin hoard found in Britain."
Work to separate and uncover the secrets of the hoard has been delayed while Mr Mahrer works on other projects and details are agreed over long term conservation plans.
A large mound containing about 70,000 coins was discovered last year by two metal detector enthusiasts.
Reg Mead and Richard Miles began their hunt after a woman told them her father had found coins in a field some years before.
After the initial work looking at the surface of the mound taken from the ground in Jersey, Mr Mahrer started the process of replicating the object.
He said: "You mix silicon rubbers up, pour them on to the hoard and it will set on there. It then records in fine details so you can use copies for microscopic work.
"It was quit scary as I told people it would be fine, there would be no damage. I had used the technique on smaller things so was really pleased it worked out well."
When decisions are made over who has responsibility for conservation, Mr Mahrer said the work would begin to separate and catalogue every item contained in the hoard.
"Because we knew the process we want to do on the real hoard involves taking apart coin by coin by coin, we knew we would lose the original appearance.
"We thought that was important because, not only is it a pretty thing, but there might be important information in its size and shape in the future," he said.
The process of making a replica revealed a number of surprises according to Mr Mahrer.
He said: "It was a bit of a bonus if slightly embarrassing, one small part of the side collapsed more than I hoped and we lost two or three coins from a small area on one side.
"Completely by chance in there we found a small gold coin and it is the first gold one we have found.
"There are about 70,000 coins in the hoard but all the ones we have found so far are a mixture of silver and copper.
"Of the ones which fell out one was a small thick gold one which is about 100 years older than the rest of the coins."
He said they had uncovered about 1% of the coins so far and five gold items had been uncovered.
"As this one about three or four coin depths fell out it leads to the question 'what else is in there'. We have only scraped the surface and we have already found five gold objects," he said.
Mr Mahrer said if they continued finding gold on that ratio, it could push up the value of the hoard.
"One gold coin on its own wouldn't add much to the value, a few hundred pounds, but if we get in and find more then who knows?"
He added: "We deliberately haven't removed any coins from the hoard yet, we are still waiting for various permissions over who owns the hoard and funding before we take it apart."
The value of the hoard was estimated at up to Â£10m when it was first removed from the ground.
Work is now under way to prepare the coins already uncovered, and the replica made by Mr Mahrer, for an exhibition at Jersey Museum next year.
The last time it went on display in 2012 the number of visitors to the museum trebled.


A fire at a discount furniture shop has caused the roof of the building to collapse, while part of a busy main road has been closed.

Fifty one firefighters are at the building on City Road, which is thought to be disused.
The road has been closed between its junction with Newport Road and The Parade and Talworth Street.
Smoke is billowing from the building and can be seen from as far away as Penarth in the Vale of Glamorgan.
South Wales Police advised people living near the site to keep their windows closed.
Jennie Griffiths, head of South Wales fire service's joint fire control, tweeted to say the blaze involves the ground and first floor of the building.
She added: "1st floor well alight - building has suffered roof collapse."
She said firefighters were working to protect adjacent buildings.
Welsh Water has sent a text message to customers in the area, warning them their water may be discoloured due to the fire service fighting the blaze.


At almost 9,000 km long, the Canadian-American border has become the fault line for Trump anxiety.

While Donald Trump has spoken about building a wall between the US and Mexico to keep immigrants out, it is Americans who may be trying to flee.
During this election's vicious campaign cycle, the idea of Americans heading to Canada became a political statement.
Celebrities like Snoop Dogg, Bryan Cranston, and Lena Dunham have threatened to move north of the border to escape a Trump presidency. When that possibility edged closer to a reality late Tuesday night, the Canadian government's Citizenship and Immigration website crashed due to what officials called "a significant increase in the volume of traffic."
Statistics provided by the government indicated over 200,000 people were trying to access the site at 11 pm when it crashed. American IP addresses accounted for some 50% of the traffic, instead of the usual 9% to 10%.
Still, few of these contemplating fleeing have actually expanded on why they want to come to the country besides the fact Mr Trump will not be head of state and that they see the country as a friendly, progressive refuge.
And if shell-shocked Americans are seeking company to pair with their misery, Canada could be a haven.
Mr Trump's election victory has left many Canadians incredulous.
"He has no political experience, he's a business man, a reality-TV star and you blink and he's the American president?" said a shocked Robert McNair, from Cambridge, Ontario about 150 km (93 miles) from Buffalo, New York.
Paul Deskin, an American tourist from Connecticut, couldn't agree more.
"I just feel like my heart's been ripped out, the country I love votes for someone with no integrity," he said. "I hope I'm wrong, and I will fight to make our country a better country, and I truly hope that Trump finds the right way to lead."
Both men were visiting Niagara Falls, Ontario, a border city and tourist hub that shares both the majestic falls and a border with New York State.
Here, and elsewhere in Canada, these cross-cultural exchanges are nothing rare.
Every day, more than 300,000 people travel across the 8, 891 km (5,525 miles) border, the longest shared border in the world.
Many people have family in both countries and, before the 9/11 terror attacks led to more security measures,  Canadians and Americans along the border often crossed it casually with little or no formal ID.
Niagara Falls Mayor Jim Diodati says the community would be happy to welcome fleeing Americans on a more permanent basis.
"We'd roll out the red carpet. But don't believe there's going to be a mass exodus," he said. "The American spirit is strong and those were emotional statements."
The mayor thinks that once everything has settled down in the US, things will not have changed as much as people think they will.
"The way I see it, things are never as bad as they seem and they are never as good as they seem," he said.
Priyanka Varkay, who was visiting from Halifax, Nova Scotia, said an influx of southern neighbours this could be positive for Canada but worries it would strain  relations Americans moved in large numbers.
"Trudeau seems to be very diplomatic, he'll find a way around it," she said.
Others are not so sure diplomacy is the best way to deal with Mr Trump.
"If he doesn't follow the rules, we'll have to stand up for ourselves," said Toronto resident Irene Landry.
She has American neighbours who moved during the George W Bush administration. In 2006, immigration from the US reached a 30-year high, according to government statistics.
"They certainly won't go back and live under Donald Trump," she said.


Palestinian Authority President Mahmoud Abbas has undergone a series of routine heart tests and all results were normal, doctors in Ramallah say.

The 81-year-old was taken to a hospital in the West Bank city after feeling exhausted and experiencing chest pains.
Doctors performed a cardiac catheterisation procedure, in which a thin plastic tube is inserted into a blood vessel to check for blockages.
Everything appeared normal and Mr Abbas was due to be discharged shortly.
"His arteries look great, and there is no need for him to stay in the hospital," heart specialist Dr Mohammed al-Batrawi told reporters.
The Palestinian leader underwent another heart procedure known as an angioplasty to open clogged arteries in 2005.
He was elected president earlier that year after the death of Yasser Arafat, with whom he co-founded the Fatah movement and helped establish the Palestine Liberation Organisation.


The Premiership's joint-record try scorer Tom Varndell has signed a new contract with Bristol until the end of the 2017-18 season.

The 31-year-old winger, who equalled Mark Cueto's 90 Premiership tries on 1 January, joined the club in 2015.
He has crossed 26 times in 37 appearances in all competitions for the club so far, helping them win promotion back to the top flight last season.
The former Leicester Tigers and Wasps man has won four senior England caps.
"I'm enjoying my rugby and the attacking brand that we are trying to play, it suits my game," Varndell told Bristol's club website.
"I'm settled in the city and there is a great spirit among the squad which is translating into our performances on the pitch in the Premiership right now."
Interim head coach Mark Tainton added: "When he is at his best, Tom is one of the most dangerous players in the league - he's a major asset.
"Tom wants to break that Premiership try-scoring record and he wants to help establish Bristol as a top-flight club.
"The key for Tom now - as a senior player in our group - is to lead the way with his performances."
Bristol are bottom of the table after 13 league games, one point behind 11th-placed Worcester Warriors.


A union has called for a rise in council tax to protect police numbers in Nottinghamshire and for officials to accept it will trigger a public vote.

It comes as Nottinghamshire Police said a 25% cut in community support officer numbers was needed to meet budget cuts.
Unison said it believed an above-2% rise in its share of council tax would be backed in a public referendum.
However, Police and Crime Commissioner Paddy Tipping said no such vote had ever succeeded.
Due to government cuts, the force is having to save Â£2.4m from its budget, he said.
The force plans to shut four police stations and five front counters but also has said it will reduce its 319 PCSOs by 72.
By law, if any part of the tax is to rise by 2% or more, the move must be put to a public vote.
Unison's Dave Ratchford said: "The commissioner himself did a consultation last year with 4,000 Nottingham residents.
"Of these, 67% said they were willing to pay additional money to protect police services and 82% said they were against further cuts."
But Mr Tipping said experience showed people would not back them in a vote.
"Just two weeks ago there was a referendum in Bedfordshire to put up the police precept and it was rejected by 70% of the population," he said.
"I don't think people will vote for an increase. I am more than happy to discuss it but there has not been one public body that has won this sort of vote."
Separately, a report from HMIC has found the force is making good progress towards achieving the savings required while maintaining an effective service to the public.


An RSPCA inspector was called out to deal with a tarantula in a house in Hampshire, only to discover it was a child's toy.

The householder had reported seeing a spider "the size of her hand" hiding in a downstairs cupboard.
Inspector Nikki Denham was prepared with gloves and nets to trap the spider, but after shining a torch in the cupboard saw it was plastic.
The RSPCA said the woman was "obviously embarrassed".
Ms Denham said the householder in Alresford had closed all doors to prevent the spider's escape before she arrived.
"It was dark under the stairs, but I could see legs behind a vacuum cleaner that certainly were tarantula size.
"However, as I shone light in I could see that it was in fact a toy plastic tarantula," she said.
She said the toy was shown to the woman's young son who confirmed it was his - "with an angelic innocent face".
A RSPCA spokeswoman said the organisation was called on to rescue 275 genuine tarantulas in 2016.


Andy Murray will hope to tighten his grip on the world number one ranking when he plays Marin Cilic at the ATP World Tour Finals on Monday.

The Briton, 29, will end the year at the top of the rankings if he wins the title at London's O2 Arena.
Murray faces Croatia's Cilic in his opening round-robin match at approximately 20:00 GMT.
"I just want to finish the year on a high note by playing well," the Scot told BBC Sport.
"If I finish number one, that's great, but that wasn't a goal of mine a few months ago. I wanted to put myself in a position to hopefully get there at the beginning part of next year."
Switzerland's Stan Wawrinka plays Kei Nishikori of Japan in Monday's first singles match at 14:00, live on BBC Two and the BBC Sport website.
Murray overtook Novak Djokovic at the top of the rankings last week and is locked in a battle with the Serb to see which of them ends the year as world number one.
Djokovic opened with a three-set win over Dominic Thiem on Sunday, and knows that two group-stage wins followed by a record sixth ATP Finals title would see him reclaim top spot.
However, Murray can deny Djokovic if the Scot wins the season finale for the first time.
"He said that it wasn't a focus to be world number one this year," said BBC Sport commentator Andrew Castle.
"But with the Wimbledon title and Olympic gold behind him, he perhaps reset himself after the US Open and just said, 'It's available and I'm going to go for it.'
"He basically won every single match for the last six weeks."
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By his own standards, Murray has a relatively mediocre 11-11 record in eight previous appearances at the ATP finale, but he arrives this year in as strong a position as ever.
He is on a 19-match winning streak, and took three days off following his Paris Masters win before practising on the newly speeded up O2 Arena last week.
"The court's definitely a bit faster than it has been in the past, so that changes the way you play the matches a little bit," said Murray.
"But I think that's a positive thing. At the end of the year, when the players have played a lot of tennis, to play on the slowest court with really, really long rallies is tough, so it will shorten the points a bit and maybe make for some better tennis."
Murray has enjoyed the best season of his career, but if he is to hold on to the number one spot he must come through the most difficult run of matches he has faced in terms of rankings.
The Briton will play world number three Wawrinka, number five Nishikori and number seven Cilic in the John McEnroe Group, with only two progressing to the semi-finals.
First up is Cilic, who beat Murray last time out in Cincinnati three months ago but has won just three of their 14 matches.
"He's been on an amazing run these last few weeks, he's going to be extremely motivated and he's going to have the crowd on his side," said Cilic.
"I just hope I'm going to continue with this good form I had the last few months."


A petting zoo in north Wiltshire claims low flying military aircraft are causing its animals great distress.

Studley Grange Farm Park and Zoo near Wroughton said planes flew over its site up to five times per day.
It said the day after a low flying jet passed overhead a ewe had aborted its lamb and a vet said the death may have been linked to the ewe's stress levels.
The Ministry of Defence, which has a site in Amesbury, Wiltshire, said low flying was essential for its training.
Boscombe Down in Amesbury, Wiltshire, is a Ministry of Defence (MoD) aircraft testing site and nearby in Salisbury Plain is a large military training area, from where numerous flights originate.
Farm manager Ms Stewart said: "The lamb had only just died and we think it was a direct result of the airplane coming over so low."
She said the ewe became stressed and would not give birth if it felt endangered, resulting in the lamb dying inside the womb.
John Fishwick from the British Veterinary Association said: "It's terribly upsetting when a sheep aborts.
"There's no doubt low flying aircraft can stress animals and cause problems, the abortion is a possibility.
He said he would recommend a post-mortem examination on the lamb to look for other possible causes of death, before reaching a conclusion.
Ms Stewart said there had been an increase in low flying jets in the past year and it was having a negative affect on its other animals too.
She said the jets caused the goats to frantically jump over fences, it made the rabbits "freeze" in terror and caused the meerkats to "sit shaking" in their houses.
The MoD said it took seriously concerns about low flying.
It said: "The MoD strives to ensure that such disturbance is kept to an absolute minimum and that it is distributed as evenly as possible throughout the UK Low Flying System as a whole."


Guernsey's hockey team have secured the biggest match in their history after progressing to the third round of the England Hockey Cup to face Premier League side Reading.

Zak Damarell scored a hat-trick as the islanders beat London Edwardians 3-1 in their second-round tie in the capital.
"It's enormous," Guernsey coach Andy Whalley told BBC Sport.
"They're an unbelievable side, they've been European champions, their pedigree is great, everyone knows Reading."
Guernsey went a goal down inside the first 10 minutes of their second-round tie, but Damarell's first goal ensured it was level at half-time.
Guernsey had to weather huge pressure from their hosts, with Adrian Gidney making a string of important saves in goal, as Damarell twice scored on the break.
The island side is made up of players from the Guernsey league and does not play in a league itself.
But they have a fine pedigree in the second-tier EH Trophy, making the last five finals, winning twice.
"We've got an awful lot of work to do, but we're excited and looking forward to it," added Whalley.
"It's a game we're not expected to win, they'll be massive favourites, but you never know what might happen on the day - we've got some wonderfully talented players in our squad."


Jaguar Land Rover (JLR) has been fined £900,000 after a worker lost his leg in a car accident.

A delivery driver lost control of a car and crashed into another car causing a four-car shunt at its Solihull plant, the Health and Safety Executive said.
The worker became trapped between two cars as he crossed a production line, causing severe injuries. Two more people were also hurt.
JLR was found guilty of breaching the Health and Safety at Work Act.
Two other workers suffered minor injuries in the incident.
More on this and other stories from Coventry and Warwickshire
Birmingham Crown Court heard the car-maker has since introduced a buffer zone to reduce the risk of a similar accident.
In a statement issued after the trial the HSE said JLR had failed to ensure the delivery driver, who was covering the shift, was familiar with normal procedures.
The firm had also failed to separate workers on the production line.
HSE inspector John Glynn said the "life-changing injuries" suffered by the worker were "completely avoidable".
"It was only good fortune that prevented this from being a fatal accident," he said.
As well as the fine, the company - whose headquarters are based in Coventry - also had to pay £49,868 costs.
A JLR spokesman said the company accepts the decision, adding it is "committed to the safety and well-being of all employees".


Londonderry's urban regeneration company, Ilex, will close by 31 March 2016 with the loss of 18 jobs.

The Office of the First Minister and Deputy First Minister (OFMDFM) made the announcement on Thursday morning.
An independent review, published in July, criticised the company's failure to bring in private investment.
The remainder of Ilex's capital work projects will be managed by OFMDFM and Derry City and Strabane District Council.
The date of closure for the company is a year earlier than recommended in an official report.
Set up in 2003, the company was tasked with the regeneration of former army bases at Fort George and Ebrington.
Ilex lists among its successes helping deliver the Peace Bridge, the City of Culture year and the Science Park at Fort George.
Last month saw the resignation of Mel Higgins, the company's fifth chief executive in its 12 year history.
First Minister Peter Robinson said: "We are grateful for all the work undertaken by Ilex at Ebrington since 2003 which has opened the site up for all the people of Londonderry and beyond.
"The reviews concluded Ilex should have a limited lifespan and its work should ultimately move to the local council - that remains the long-term plan.
"However, in the short-term, given the recent resignations of the entire senior management team, we have decided that the development of Ebrington will be led by OFMDFM."
Deputy First Minister Martin McGuinness said: "The intention that the council should take responsibility for the Ebrington site to deliver the capital works remains our preferred option which we would wish to see achieved by 2017.
"The company will be closing by 31 March 2016 and all affected staff will be eligible to receive any redundancy entitlements."


Sixteen republicans received royal pardons between 2000 and 2002, the Northern Ireland Office has disclosed.

The NIO gave fresh details about when the pardons were given after Tuesday's confirmation by Sinn Féin's Gerry Kelly that he too was a recipient.
It said the current government had not used the Royal Prerogative of Mercy in relation to Northern Ireland.
The pardons allow changes in sentences without the backing of or consultation with parliament.
The NIO said those issued between 2000 and 2002 were "in relation to individuals who for technical reasons fell outside the letter of the [prisoner] Early Release Scheme".
Earlier, North Belfast MP Nigel Dodds asked the prime minister to release all the names of republicans who were granted royal pardons.
Mr Dodds raised the issue in the House of Commons. David Cameron said he would consider what more the government could do to be transparent.
He added that past governments had had to make difficult decisions for peace.
Last year, Secretary of State Theresa Villiers disclosed that 365 royal pardons had been issued between 1979 and 2002. It is not clear how many of those pardoned were members of paramilitary groups, or what proportion, if any, were members of the security forces.
In the Commons on Wednesday, Mr Dodds asked: "Would the prime minister now list in the library of the House all those other Sinn Féin members and leading republicans who have likewise received a royal pardon, so that republicans in Northern Ireland can know which of their stalwart leaders have either begged or asked or received probably on bended knee such a royal pardon - and secondly, so that everyone can know in the country which governments have been involved in such nefarious activities?"
Mr Cameron replied: "I will look very carefully at what the member asks and what more we can do to be transparent."
He went on: "Governments in the past have had to make difficult decisions with respect to Northern Ireland to try to bring parties together and produce the peaceful outcome we have today.
"That has involved difficult compromises and things that he and probably I have found at times deeply distasteful. But sometimes in the pursuit of peace these things have to be done."
Mr Kelly was arrested in the Netherlands in 1986, about three years after he escaped from the Maze prison.
The British authorities applied to extradite him, but the Dutch Supreme Court would not allow it on the basis of charges for which he had already been convicted.
However, they did allow the extradition to go ahead on the basis of several charges that the British authorities wanted to bring in relation to the Maze escape.
According to a Sinn Féin source, the UK government chose to use the Royal Prerogative of Mercy in order to quash his convictions that pre-dated the Maze escape, in order to extradite him to face charges in connection with the escape.
Upon his return to Northern Ireland, he spent another few years in jail.


Former Conservative chancellor Geoffrey Howe has died at the age of 88 after suffering a suspected heart attack, his family has announced.

Lord Howe, Margaret Thatcher's longest serving cabinet minister and chancellor from 1979 to 1983, died on Friday.
His resignation speech in 1990 is widely seen as a key factor in Baroness Thatcher's downfall as prime minister.
Prime Minister David Cameron led tributes, saying: "The Conservative family has lost one of its greats."
The former MP for the East Surrey, Reigate and Bebington constituencies, played a "vital" role in "turning the fortunes of our country around" as chancellor, Mr Cameron added.
Lord Howe's family said he died at his home in Warwickshire after attending a jazz concert with his wife Elspeth.
'Reforming and innovative chancellor': Lord Howe Obituary
Tributes to ex-chancellor Geoffrey Howe
During his time as an MP, Lord Howe also served as Mrs Thatcher's foreign secretary, deputy prime minister and leader of the House of Commons.
But BBC political correspondent Robin Brant said his resignation as deputy prime minister - shortly after Mrs Thatcher declared that the UK would never join a single currency project - had been a "devastating blow" to her premiership.
In a famous speech to the Commons, he used a cricket metaphor to describe Mrs Thatcher's attitude to British negotiations in Europe.
"It is rather like sending your opening batsmen to the crease, only to find... that their bats have been broken before the game by the team captain," he said.
Mrs Thatcher resigned shortly after, later saying he had become a "source of division and a focus of resentment".
BBC political correspondent Robin Brant
A wolf in sheep's clothing - Geoffrey Howe was mild mannered and modest with a steely conviction. In the end he was unwilling to let Margaret Thatcher ride roughshod over him.
Denis Healey once famously said that being attacked by him was like being "savaged by a dead sheep". Yet Lord Howe proved devastating when he rose to make his resignation speech in the Commons after he quit the cabinet in protest at the then prime minister's approach to Europe and diplomacy.
His cricket analogy revealed the deep frustration many felt about what they had come to regard as an autocratic leader (who was already on the wane). With that the "dead sheep" inflicted the first blow.
He will be regarded as the man who delivered the radical changes that transformed the UK in the 1980s, by both those who regard that as a good thing and those who don't.
Mr Cameron described Lord Howe - who retired from the Lords in May - as "the quiet hero of the first Thatcher government".
"Geoffrey Howe was a kind, gentle and deeply thoughtful man - but at the same time he had huge courage and resolve," the prime minister said.
Chancellor Osborne tweeted: "I will miss Geoffrey Howe. He was a great source of advice to me; a quietly-spoken radical, whose bitterly contested budgets rescued Britain."
Sir John Major, who succeeded Lady Thatcher as prime minister, said Lord Howe "was a man whose political convictions, turned into law, transformed our nation".
He added: "Geoffrey has left a benevolent mark on our national life, and I hope in death will receive the credit so often denied him in life."
Other former Conservative chancellors were among those paying tribute. Lord Lamont praised him as a "Tory with a social conscience, who wanted opportunity for all".
Ken Clarke said: "He had very strong views about how best to serve the national interest - that's what he saw himself as doing, and having thought through his views with a very good, clear intellect he then stuck to them and succeeded in delivering them."
Former Deputy Prime Minister Lord Heseltine said he had been a "political rock".
"He carried huge personal strain for the success of that government," he added.
"They were very controversial times, controversial policies, but Geoffrey was unbending and unyielding but he was a very kind, courteous and gentle man."
Welsh Secretary Stephen Crabb said Lord Howe - who was born in Port Talbot - had been a "towering" political figure who always had a great affection for Wales.
Labour leader Jeremy Corbyn tweeted: "I got to know Geoffrey Howe when he was Foreign Secretary and valued his knowledge and experience. Condolences to Elspeth and family."
And Labour's shadow chancellor John McDonnell said: "Lord Howe devoted his life to the service of his country and did so with distinction.
"He was not afraid to stand up for what he believed in and famously demonstrated this in his historic confrontation with Mrs Thatcher."
Liberal Democrat leader Tim Farron described Lord Howe as a "kind, decent and honourable man".
A statement from Lord Howe's family said a private family funeral, followed by a memorial service, would take place in due course.