REPEATED sightings of UFOs over Bristol were dismissed as probably nothing more than a laser display that posed no threat, documents by the Ministry of Defence reveal.

The MoD documents, released today, also show that a Withywood teenager who claimed to have been abducted by alien beings soon after the sightings in 1996 was told to go to police as abduction was a "non-issue" for the MoD.

These and other allegations of political cover-ups, UFO sightings and bizarre finds from the past 60 years from across the UK are in the papers from the National Archives.

In July 1996 a giant double circle of up to 26 lights was seen hovering over Bristol by several witnesses and several reports led the MoD to check with air defence experts.

One middle-aged couple and their daughter reported it as hovering over flats in Bedminster, making a whirring noise. One young man in Montpelier watched it moving backwards and forwards for three hours from 2.30am on July 6. Another witness thought it disappeared behind clouds in St Paul's. A 28-year-old woman from Whitehall watched it rotate.

Reports of sightings were also made from people in Clifton, Kingswood and Ashton. Several witnesses sent sketches.

It is believed interest in UFOs may have intensified at the time because Hollywood blockbuster Independence Day, about an alien invasion of Earth, was the biggest film of the year.

Chris Davies, of the Search UFO group, even made his own investigations after hearing the rumours and collected several eyewitness accounts before contacting the MoD.

But the MoD's air defence experts were confident there had been no breach of UK air defence and noted that the sightings had "possibly been caused by a laser display."

Shortly afterwards on September 9, 1996, a 17-year-old writing from Withywood said he or she had "experienced many physical and psychological phenomena, and have also endured since the age of five, very traumatic experiences (often called 'abduction' with 'non-human entities.')"

The letter asked whether the ministry was responsible for protecting the public from the "potentially dangerous" manifestations. The response was that alien abduction was a "non-issue" for the MoD and "as abduction is a criminal offence, that is a matter for the police and the Home Office."

Dr David Clarke, author of a book on sightings called The UFO Files and senior lecturer in journalism from Sheffield Hallam University, said the papers showed how reactions to UFO sightings had changed over the years.

He said: "These papers demonstrate how far official policy towards UFOs changed after the Cold War.

"In 1957, some officials were so concerned by a spate of incidents involving UFOs the subject was placed on the agenda of the Joint Intelligence Committee (JIC)."

Nick Pope, a former MoD civil servant who worked on the official UFO files, said: "Whatever you believe about UFOs, there's some fascinating material in these real-life X-Files.

"Most of these sightings turned out to be misidentifications of things like aircraft lights or meteors, but a small proportion could not be explained."

Anyone can access the files free for the next month at www.nationalarchives.gov.uk/ufos.