A self-styled Muslim cleric and former leader of the radical group Al-Muhajiroun, Omar Bakri lived in Britain for 20 years before leaving for Lebanon in August 2005.
At the time of his departure he was facing a possible charge of incitement to treason. He was later banned from returning to Britain after the government declared his presence "no longer conducive to the public good". The subject of much criticism within the British Muslim community, Bakri is not believed to have been directly involved in terrorist plots but is alleged to have provided religious encouragement and justification.
In February 2003 he told people to stay away from "airports, government buildings and financial institutions" and in a later interview with a Portuguese magazine, he predicted that London would be attacked. "It's inevitable because several [ attacks] are being prepared by several groups," he said.
He claims to have provided religious instruction to two Britons who carried out a suicide bombing in Israel that killed four people in 2003. His contact details were found on a mobile phone carried by one of the bombers. He is alleged to have said afterwards that they "will now go to paradise".
Mohammad Babar, an al-Qaeda-linked supergrass who has pleaded guilty in the US to terrorism offences, told a court last year that he was influenced by radical preachers including Bakri.
A BBC Newsnight report last year alleged that Bakri advocated a terrorist attack on Dublin airport during an internet chatroom discussion with his followers.