A son and a stepson of the Egyptian-born imam, Sheikh Abu Hamza, have been named by Yemeni authorities as being part of an alleged plot to blow up Western targets in Yemen, including the British consulate.
One of the sons, Mustapha, is being sought by the Yemeni authorities, who say he fled after learning he was being hunted. Sheikh Hamza's stepson, Mohsen Ghailan, is being held with four other Britons by officials in Aden who believe they have uncovered a terrorist plot.
Last night, Sheikh Hamza, who lost his hands and the sight of one eye while defusing a mine in Afghanistan, where he was an Islamic fighter, said: "I am convinced he has been tortured to admit to things he has not done. I am waiting to see a picture of him."
He had not seen Mustapha for at least six weeks when he left Britain to travel to Saudi Arabia to pursue his Islamic studies.
But Sheikh Hamza's links to the affair go further than that. Operating from the North London Central Mosque in Finsbury Park, or from his home in west London, Sheikh Hamza, 41, runs an organisation called Supporters of Shariah that acts as a mouthpiece for a range of Islamic groups, including some that have turned to terror. He spreads the word of jihad with a vitriolic website, pamphlets and training courses for radicals.
The sheikh, who also uses the name Hamza al-Masri, confirmed yesterday that when the 16 tourists were kidnapped on 28 December, he received a satellite phone call from the kidnappers' leader, Abu Hassan, who said he had taken them to put "pressure on America and Britain to stop the oppression in Iraq and Palestine". He added: "He said he hoped he would not do it [shoot the tourists] but make it a negotiated matter."
Sheikh Hamza makes no apologies for acting as a mouthpiece for groups that use violence. "We speak for all different Islamic groups if we think they are justified in using force in the fight for Islam. We don't care what other people think of them."
Scotland Yard's anti-terrorist branch yesterday confirmed that it was "aware" of Sheikh Hamza, but declined to elaborate.
Other Muslims are also concerned. A local who used to use the Finsbury Park mosque said it had been "taken over" by the sheikh. At the nearby Muslim Welfare House, which also doubles as a mosque, a receptionist said they refused to stock Sheikh Hamza's pamphlets. "We do not agree with his views," he said.
Sheikh Hamza and his friends paint a different picture. The sheikh says he studied civil engineering, first in the Egyptian city of Alexandria, and then at Brighton University in East Sussex. The university was yesterday unable to confirm he had been a student. The sheikh's associate, Sheikh Omar Bakri Mohammed, said he provided training for young Islamic scholars.