Six men were arrested by counter-terrorism officers yesterday over speeches made two-and-a-half years ago at a mosque.

The men, including Abu Izzadeen who heckled Home Secretary John Reid at an event last year, were held early yesterday over statements apparently made at Regent's Park Mosque in London in November 2004.

Scotland Yard said they were detained in an investigation into incitement of others to commit acts of terrorism overseas and into terrorist fundraising.

Last night, leaders of the mosque distanced themselves from the men, aged between 21 and 35, who were arrested at addresses in east London, Southall and Luton. They were being held at a police station in central London.

The arrests came on the same day Tony Blair warned terrorism continued to be a global threat, before he and cabinet colleagues were briefed by the new head of MI5 on the terror threat facing Britain.

A spokesman for Scotland Yard said last night said: "The arrests form part of a long-term and complex investigation into alleged incitement and radicalisation for the purposes of terrorism, as well as alleged provision of financial support for international terrorism."

Mr Izzadeen, 31, who was born Trevor Brooks into a Christian-Jamaican family in Hackney, is best known for his heckling of the Home Secretary last September. At a speech to British Muslims in London, Mr Reid was interrupted by Mr Izzadeen, who called him "an enemy of Islam" and "a tyrant", accused the government of state terrorism and said Mr Blair and US President George W Bush could "go to hell".

He was also arrested in east London last February by officers from Scotland Yard's anti-terror unit over a speech he made in Birmingham last year in which he allegedly praised the July 7 bombers.

Outspoken Muslim scholar Anjem Choudary yesterday confirmed his "close friend" Mr Izzadeen had been arrested. He said: "There were six arrests this morning, around 5 or 6am. They are saying it's in relation to something around November 2004, allegedly collecting funds for terrorism, inciting terrorism."

After the arrests, Ali Khan, estate manager and head of security at Regent's Park Mosque, said: "We don't like it if people come here and disturb the peace of the place. We want it to be peaceful for people to come and worship.

"Ten thousand people come here every week and if a few people create a disturbance, it puts us in an embarrassing situation. Abu Izzadeen has frequently visited and worshipped here but if he excites the crowd, we don't like that."

Before Mr Blair and his colleagues were briefed by new MI5 head Jonathan Evans, the Prime Minister said terrorism needed to be fought, whether it was in "Iraq, Afghanistan or anywhere else".

He told the BBC his view was "not popular" but the "large part of the Western world" which blamed Mr Bush was wrong.

"This is a very deep-rooted problem right round the world. If we don't fight it it's going to come after us," Mr Blair said.

Mr Evans delivered his briefing at the first meeting of the government's new committee on security and terrorism.