The man at the centre of a protection of sources case has revealed his identity at a press conference.

Journalist Graham Smith's previously anonymous source, with fresh evidence on the 30 year mystery of the sinking of The Gaul, went public at the conference at Trinity and All Saints journalism training college in Leeds.

The source, now known to be retired Royal Navy Chief Petty Officer Derek Barron (right), gave evidence supporting the theory that the trawler was dragged over by a Navy Polaris nuclear submarine.

The trawler was lost off the Arctic coast of Norway in 1974 with the loss of 36 lives.

He told the press conference that he had overheard a Royal Navy submarine warrant officer confess to accidentally dragging over the Gaul while on patrol in a British nuclear sub.

"He specifically named the trawler as the Gaul, of that there is no doubt in my mind," said Derek, who served with the submarine service for 15 years from 1980.

He made his identity known after assurances he would not be prosecuted under the Official Secrets Act or jeopardise his services pension.

His evidence could have been given to a Public Inquiry into the sinking if he had shed his anonymity.

He has already given the evidence - anonymously - on the website of Yorkshire freelance Graham (pictured left).

And he has now faced the families of the 36 men who died at a meeting of the Gaul Families' Association, which is still looking for answers to the Barents Sea mystery.

The solicitor to the inquiry for the Government, Laurence O'Dea, travelled to Leeds to hear Derek's evidence.

Afterwards he said it "may or may not" lead to the inquiry being reopened.

'Hearsay' theories at such public meetings are outside the confines of the inquiry itself, and in this instance were made before there had been an opportunity properly to investigate and test them.

But he said he would take a statement and then seek advice from Wreck Commissioner Mr Justice David Steel, who headed the inquiry.

Last month Mr O'Dea issued a summons for Graham to reveal his source and/or send his statement to him. The journalist refused, and the summons was eventually dropped.

The source had been scheduled to appear anonymously at the press conference via a live audio link up to protect his identity. But the day before, Mr O'Dea gave the necessary assurances and Derek was able to appear in person.

Before the meeting the solicitor had appealed for the submariner to make his views public, and said: "If anyone has information relevant to the loss of the Gaul the only proper manner of dealing with such information is to provide it to the inquiry so that it may be thoroughly and properly investigated and considered by the Wreck Commissioner along with all the other evidence that he has heard."

He added that the families could be assured that the Wreck Commissioner was considering possible loss scenarios involving a submarine, but could not investigate the particular claims of the former chief petty officer unless he provided evidence to the inquiry - something he had not been willing to do.

The former Navy officer told the families he had overheard a conversation at a Royal Navy training centre in Portsmouth that another officer said a British Polaris nuclear submarine had become entangled with the Gaul, causing it to sink.