English Defence League warns UK could face attacks

As further details emerged of the connections between Anders Behring Breivik and the English Defence League (EDL), the group's founder warned last night that a similar attack could take place in Britain.

The group strenuously denies any knowledge of Breivik, and has unreservedly condemned the murders, but a number of members of the anti-Islamic organisation claimed he joined a rally in London last year. The anti-fascist group Searchlight is preparing to release further information today about the killer's links with the EDL.

The allegations surfaced as police and security services began urgently examining the activities of far-right organisations following Breivik's claims to have met like-minded extremists in London. Security sources said that was no immediate evidence backing up his claims he had a support network that extended to Britain – and there is little history of links between British and Norwegian neo-Nazis.

The EDL was the organisation mentioned most often by Breivik in the 1,500-page personal "manifesto" he posted online before embarking on his killing spree. Stephen Lennon, its leader, said he did not believe the Norwegian had ever marched alongside EDL activists. EDL organiser Daryl Hobson wrote in an online posting: "He had about 150 EDL on his list ... bar one or two doubt the rest of us ever met him, altho [sic] he did come over for one of our demo [sic] in 2010 ... but what he did was wrong. RIP to all who died as a result of his actions."

However, a senior member said he understood Breivik had met EDL leaders when he attended the demonstration in March 2010, and described him as "very affable". "I spoke to him a few times on Facebook and he is extremely intelligent and articulate and very affable," the source told The Daily Telegraph. "He is someone who can project himself very well and I presume there would be those within the EDL who would be quite taken by that. It's like Hitler, people said he was hypnotic. This guy had the same sort of effect."

In his first public appearance since the attacks, Mr Lennon said similar attacks could take place in the UK if the right of peaceful protest was taken away. He told BBC2's Newsnight: "You need to listen because, God forbid, this ever happens on British soil .... it's the time coming ... you're probably five or 10 years away."

The Independent has also learned that Lena Andreassen, the leader of the Norwegian Defence League, a group that Breivik claimed to have co-founded, attended an EDL demonstration in May last year. A picture taken from a photo-sharing site shows Ms Andreassen wearing a steward's vest at the demonstration, suggesting contact with organisers of the march.

Breivik's boasts of forging contacts in Britain have prompted a wide-ranging review of activity by far-right groups associated with violence. The security checks were ordered yesterday at a meeting of the National Security Council, chaired by David Cameron. Detectives are examining whether there is any suggestion that former members of neo-Nazi groups are trying to regroup.

A hardcore of activists on the extreme right accuses the British National Party of selling out by embracing electoral politics. Police are now investigating whether any have turned to violence or made links with terrorist organisations in Europe or North America.