A prime suspect in the second wave of London bombings has told Italian detectives he took part in the attacks on the city's transport system as British police quizzed three other suspected bombers yesterday.

A judicial source with direct contact to the man confirmed Italian media reports that Osman Hussain, arrested in Rome on Friday, has said he participated in the July 21 failed attacks.

"Yes, yes. I can confirm that," the source said. He gave no further details.

Mr Hussain's court-appointed lawyer Antonietta Sonnessa told Britain's ITV news that Mr Hussain had no links to the July 7 bombers and had no idea where his explosives came from. "He is not a violent person. He did everything possible to ensure his actions did not provoke any injuries, damage or death."

Dr Sonnessa added Mr Hussain was not a suicide bomber.

"He was not a kamikaze, he did not want to blow anything up at all. He cannot give any help to police for the simple fact that he is not associated with any terrorist organisation."

Police arrested seven further men and one woman yesterday in southern England under anti-terrorism laws in connection with the July 21 attempted bombings but a police source said the arrests were not a significant development in the inquiry.

That brings the total number of people being questioned by British investigators in relation to the probe, the biggest operation for London's police since World War II, to 19. Dr Sonnessa has also suggested Mr Hussain, an Ethiopian-born British citizen, may try to resist extradition to Britain.

London police believe they have captured all four men they were seeking over the July 21 botched bombings on three underground trains and a bus, which came two weeks after four bombers killed themselves and 52 people in similar attacks.

After an international manhunt for suspected Islamist militants which culminated in a swoop on a housing estate in west London on Friday, three of the men are in custody in London and the fourth in Rome.

Officers, who warn of new strikes, are still looking for anyone who may have helped the bombers.