Rendlesham Forest UFO: Are we any closer to the truth 40 years on?

US servicemen reported seeing a UFO in Rendlesham Forest, Suffolk, just outside their base, a scene mocked up for a documentary

Forty years ago, a remote forest in Suffolk was the scene of one of the most famous purported UFO sightings in history. So just what did happen, and will we ever know for sure?

Vince Thurkettle was out chopping wood one morning in Rendlesham Forest in late December 1980 when a car drew up.

Out stepped two men, aged about 30, dressed in suits.

"Good morning. Do you mind if we ask you some questions?" asked one, in a well-spoken English accent.

Earlier, on 26 and 28 December, United States Air Force (USAF) security personnel stationed at nearby RAF Woodbridge had reported seeing strange lights in the surrounding forest.

Vince Thurkettle, now 64, was a forestry worker at the time of the incident

Forestry worker Mr Thurkettle's unannounced - and unidentified - visitors asked if he had been out the previous night. "I said: 'No,'" he recalls.

"They said 'Did you leave the house at all? Did you see anything?' I said: 'What?'

"They said: 'Oh, there's a report of some red lights in the forest... We're just checking.' And the two of them, very politely but firmly, asked me probably about 20 questions. I thought they were journalists.

"They suddenly said: 'Oh well, fair enough. There's probably nothing in it.' And left.

"So, I bought the papers every day for the next few days to find out what was going on and, of course, there was nothing."

Lt Col Charles Halt was one of the servicemen who claimed to have witnessed the UFO at Rendlesham Forest

Three years later, however, the sighting made a News of the World front page story. It proclaimed: "UFO LANDS IN SUFFOLK, And that's OFFICIAL"

The story was based on a memo from RAF Woodbridge deputy base commander Lt Col Charles Halt to the Ministry of Defence (MoD).

It was released by the US government and described an encounter with an apparent UFO in the forest.

Information boards in Rendlesham Forest guide visitors around key locations in the story

Since then, the sighting has been the source of much debate and speculation among UFO enthusiasts and the subject of numerous books, articles and TV programmes.

In March, a documentary concluded the sighting had achieved "legend" status, like Loch Ness or King Arthur.

The forest even has its own official UFO trail, complete with a life-size replica of a flying saucer.

The Forestry Commission has set up a UFO Trail in Rendlesham Forest, featuring a model based on what the USAF personnel claimed to have seen

Mr Thurkettle says the UK authorities have said they did not learn about the incident until Halt's memo.

But the memo was not written until two weeks after he received his visit, he says.

"So someone must have told them before," he says.

Only after the visit did Mr Thurkettle began to hear rumours of a UFO sighting in the forest.

Mr Thurkettle says he saw nothing unusual when he visited the scene of the supposed sighting

He begged his boss to show him the scene, but when he got there, "my heart absolutely plummeted", he says.

"It was nothing. It was an absolutely normal glade in the forest with three rabbit scrapes, and they're all carefully marked, that happened to be roughly in a triangle," he says.

"I mean, there was a ring of sticks around it, marking it. And I think, fair-do's to the Americans.

"If they'd been out at night and saw a light and came back in the daytime looking for something, I could totally understand why they... said: 'This must be it.'"

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As a "countryman born and bred", however, he saw nothing unusual.

"It was a completely natural glade. And they've said things like: 'But there were broken branches.' Well, the forest is full of broken branches.

"They saw burn marks on the trees. They said: 'Obviously there was heat radiating out from the spacecraft and it burnt these trees.' But it wasn't. It was one of the rangers, Bill Briggs, with an axe."

Mr Thurkettle, now 64, was one of the first people to suggest an alternative theory to explain the sighting.

Could the beam from Orfordness Lighthouse explain the UFO sightings?

It took place, he says, in the only part of the forest where it was possible to see the since-dismantled Orfordness Lighthouse.

"It's weird because you've got a slightly sloping patch of Rendlesham Forest. Then, probably a couple of miles, then Gedgrave Hill. And there was a gap in the trees on Gedgrave Hill, then eight miles or whatever to Orfordness Lighthouse.

"UFO believers have talked to lighthouse keepers who said: 'It never beamed towards the land'. And I think: 'Rubbish'.

"I've stood in the beam of the lighthouse. I've looked at it and the forest."

But who were Mr Thurkettle's mysterious visitors? He isn't sure, but he gets annoyed when people assume he is claiming to have been visited by the fabled "Men in Black", who, it is said, interrogate and harass UFO eyewitnesses.

"I say: 'Oh, that isn't what I'm saying. I'm telling you that the chronology which is part of this story - it's wrong.'"

USAF security guard John Burroughs drew a sketch of what he says he saw on 26 December 1980

Journalist and academic Dr David Clarke, whose requests led to the MoD's file on the Rendlesham incident being released, says the most "logical explanation" was that Mr Thurkettle's visitors were local newspaper reporters, who had possibly learned of the incident from local police.

He says the original sighting by USAF security guards has not been fully explained.

"There is still an element of mystery. What happened to those three guys on the first night I still find baffling. Maybe they did see something that was inexplicable," he says.

One of those guards was John Burroughs. He went to investigate the sighting, and says he first saw a beacon in the distance in the forest with green, red, orange and white lights.

RAF Woodbridge closed in 1993

As he and his colleagues approached, Mr Burroughs says they saw a white light silently explode and then a red, oval, sun-like object in the clearing. It lifted up through the trees and shot back towards the coast.

Mr Burroughs, who served in the US armed forces for 27 years, says: "It's been a crazy 40 years [since the encounter]. Just when you think the story is over, another thing happens."

This month he has published a new book - Weaponization of an Unidentified Aerial Phenomenon - in which he outlines research that, he says, shows the incident was caused by experiments in harnessing an energy field in the forest.

"They were studying the energy field for different applications to include military use," he says.

Mr Burroughs claims the lighthouse was "emitting EM (electromagnetic) frequencies towards Rendlesham Forest".

He stresses: "I never went on the record to say it was [a spaceship] because I didn't know."

What he saw was some sort of energy or "plasma which could be a form of intelligence", he says.

Rendlesham Forest has a UFO Trail for visitors to explore

Dr Clarke, writing in a blog, has interviewed Ministry of Defence (MoD) official Simon Weeden, who told him the Rendlesham claims were found to be of "no defence significance".

Mr Weeden, who left the MoD in 1988, was the first to investigate Lt Col Halt's memo.

"Nearly always the reports we got were from ordinary members of the public," he tells Dr Clarke. "This one was very unusual in that it came from a military source."

He circulated the memo but none of the radar stations checked reported anything unusual on their logs over the Christmas holidays.

"Once we had been through all the basic checks and found there was nothing seen on radar - no obvious explanation, no obvious threat to air defence - we decided no further action was needed," says Mr Weeden.

Brenda Butler (filmed in Rendlesham Forest in 2000), who was one of the first to investigate the case, regularly returns to forest

Writer Brenda Butler, of Leiston, Suffolk, has been amused by some of the UFO tourism that has grown up around the forest.

"You realise we've got eight landing sites down here," she says.

"Everybody has got their own take on it. If you go down there with any of the witnesses, they'll take you to somewhere else."

Ms Butler, who co-wrote the 1986 book on the case, Sky Crash, believes the US may have recovered a Russian satellite.

"It has got to be something to do with the Americans or the Russians or the Cold War," she says.

"There are loads of files still to be released, but there has been such a big cover-up, nobody will ever know what happened.

"I'd like to get to the bottom of it all but I guess we never will."