Loyalist killer Michael Stone shouted as he was led from the dock yesterday after being found guilty of attempting to kill Gerry Adams and Martin McGuinness.

As he was taken down to the cells he denounced the judge’s ruling as a sop to republicanism.

“It’s another concession to the Shinners (Sinn Fein),” he snarled.

The outburst came after the 53-year-old was convicted of trying to murder the senior republicans when he launched a bizarre one-man assault on Parliament Buildings armed with explosives, knives, an axe and garrotte.

The former UDA member, who gained notoriety in 1988 when he killed three mourners at an IRA funeral in west Belfast, claimed his actions at Stormont in November 2006 were all part of an elaborate performance art display. Delivering his judgment in the non-jury trial at Belfast Crown Court, Mr Justice Deeney rejected this theory as being “wholly undeserved of belief”.

The judge said the idea that Stone was taking part in some sort of a “comic parody” was “hopelessly unconvincing” and “self-contradictory”.

“I am satisfied that Mr Stone went to Stormont to try and murder the two Sinn Fein leaders on November 24 2006,” he said.

Television cameras in situ to cover political developments in the stalling Northern Ireland peace process captured the moment Stone burst through the revolving doors and was hauled to the ground by two security guards — both of whom were later honoured for their bravery.

As well as the two attempted murder charges, he was convicted on seven other counts, including possession of nail bombs, three knives, a garrotte and axe, as well as causing criminal damage to the Stormont building.

Dressed in trademark denim jeans and jacket, but now shorn of the long hair he sported during the Troubles, the father of nine cut a pathetic figure as Mr Deeney read through his two-and-a-half hour judgment.

Now crippled by arthritis, the one-time loyalist icon had to be helped from the dock when the verdict was finally delivered.

And there was only a handful of people in the large public gallery to hear his parting rant as he was taking away.

Stone, who was released from prison on licence under the terms of the 1998 Good Friday Peace Agreement, will be sentenced on December 1.

During the four-and-a-half-week trial, his defence lawyers had argued that the weapons he had armed himself with were merely “props”. They claimed letters he had posted to two journalists on the morning of the attack outlining his intention to kill the senior republicans were also part of his “script”.

The piece of interpretative theatre was designed to expose the hypocrisy of local politicians, the multiple killer had claimed.

But Crown prosecutors dismissed these theories as nonsense, accusing Stone of dreaming them up after the event in a bid to explain away murderous intentions.

The judge concurred and said the defence had failed to put any doubt in his mind that Stone had set out to kill the republicans.

He asked if it was only supposed to be some form of act then why had Stone admitted his desire to kill the men during police interview after his arrest.

“If this had really been a mere protest, that was the time to tell the police,” he said.

Instead, the court heard that during interview Stone told police: “I went to the Parliament Buildings today specifically to assassinate Gerry Adams and Martin McGuinness and to disrupt an event that was betraying us.”

He branded the Sinn Fein leaders war criminals.

“I would have got in and stabbed Adams and McGuinness, cut their throats,” he told officers. I am not ashamed of where I went today. I was willing to give my life for my beliefs if I had to and take life, that is why I was there.”

The judge added that even if Stone was acting, that was no justification for criminal behaviour.

“It is clear to me that a claim that some actions constitute performance art cannot justify the use of violence, the threat of violence or putting others at risk of violence,” he said.

“A desire to shock in the sense of surprise should never prompt that fear. It might be thought that it was antithetical to the very nature of art, however, defined.”

Judge Deeney said he was satisfied with the evidence of explosives experts that nail bombs and incendiary devices carried by Stone were viable.

The event happened four months before the historic power-sharing deal between Sinn Fein and the DUP, on the day Ian Paisley and Martin McGuinness were due to be nominated as Northern Ireland's new First and Deputy First Ministers.

Stone had applied make-up and trimmed his moustache because he thought he would look better if his attack was on camera.

The killer, who on release from jail eight years ago tried to reinvent himself as an artist, then sprayed red paint on the pillars of Parliament Buildings but was disturbed by a security guard and pointed a replica gun at him.

The man described zigzagging away from him and raising the alarm. The loyalist then attempted to force his way through the revolving doors, but was trapped by security guard Sue Porter.

She wrestled the replica gun from him, but he was able to light a fuse on one of the bags he was carrying and throw it into the hall, warning that it would explode in five minutes.

While guilty of a total of nine counts, Stone was acquitted of one charge of possession of explosives with intent to endanger life and another of assault causing actual bodily harm.