An outspoken Islamist extremist who shouted down John Reid, the former Home Secretary, at a public meeting has been convicted of terrorist fundraising and inciting terrorism overseas.

Abu Izzadeen, a convert to Islam, was found guilty by a jury at Kingston-upon-Thames Crown Court after a trial lasting more than three months.

Five other men who stood trial alongside him were also convicted of terror offences.

Abu Izzadeen was not tried over his disruption of Mr Reid’s meeting, but because of the inflammatory content of a speech he made at Regent’s Park Mosque in 2004.

Video of the speech was found by police in a raid on the home of the exiled cleric Omar Bakri Mohammed.

Abu Izzadeen, who was born Trevor Brooks in Hackney, East London, was former disciple of Bakri Mohammed and a leading figure in his al-Muhajiroun movement.

He was the child of Jamaican immigrants and changed his name to Omar Brooks after his religious conversion before later adopting Abu Izzadeen and styling himself as a preacher.

When Bakri Mohammed left Britain to live in Lebanon, Abu Izzadeen became more prominent and increasingly vociferous. He frequently mocked the victims of terrorist attacks in his speeches.

He told one radio interviewer that the 7/7 attacks were a sign that the West should “wake up and smell the coffee”. In another interview he said the suicide bombings, in which 52 innocent people were killed, had been “completely praiseworthy”.

The former electrician became infamous in September 2006 when, as Mr Reid addressed a public meeting in Leyton, East London, he stood up and drowned out the minister’s speech.

Abu Izzadeen shouted: “How dare you come to a Muslim area when over 1,000 Muslims have been arrested? You are an enemy of Islam and Muslims, you are a tyrant. Shame on all of us for sitting down and listening to him.”

One of those convicted with Abu Izzadeen was Simon Keeler, 35, from Whitechapel, East London, who was also known by the name Sulayman. He is thought to be the first white convert to Islam to be found guilty of terror offences.

Brooks and Keeler were found guilty of fundraising for terrorism along with Shah Jalal Hussain, 24, - who absconded during the trial after being admitted to hospital - and Abdul Muhid, 24. Brooks, Keeler, Abdul Saleem, 31, and Ibrahim Hassan, 21, were convicted of inciting terror abroad.

The jury deliberated for more than 22 hours before returning its verdicts. In addition to the six guilty decisions, one defendant was cleared and the jurors failed to reach a verdict on another.

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