Police questioning London bomb suspects

LONDON/ROME - British police are questioning four prime suspects behind failed London bomb attacks, aiming to pin down any links to a wider network that they fear could strike again.

On Friday, police swooped on a housing estate in west London, arresting two men who identified themselves as Ibrahim Muktar Said and Ramzi Mohammed.

They were forced to strip to show they had no explosives strapped to them before being taken away.

Italian police arrested a third man in Rome who was named as Hussain Osman. He will be extradited back to Britain having left the country after the attacks.

Police arrested Yasin Hassan Omar, suspected of trying to explode a bomb on the underground, earlier this week.

Police sources said they believed they had rounded up all four men suspected of trying to explode bombs on London's transport system last week after images of them were released to the public in recent days.

The abortive attacks on July 21 took place two weeks after four British Muslims killed themselves and 52 others in blasts on three underground trains and a bus in London.

Anti-terrorist police chief Peter Clarke said on Saturday morning NZ time: "The investigation... is still continuing. It is dynamic and it is wide-ranging. There will be more very visible police activity."

"We must not be complacent. The threat remains, and is very real," he said.

Police chiefs are not yet certain if others involved in the failed explosions are still at large nor whether other militants may be planning separate attacks.

A fifth bomb was found abandoned in bushes two days after the failed attacks.

"This is the biggest investigation in the history of the Metropolitan Police and it has been conducted with extraordinary speed and professionalism," London Mayor Ken Livingstone said.

Another man was arrested in the Notting Hill area on Friday but his connection to the investigation was unclear. Before Friday's arrests, some 20 people were already being held in connection with the failed July 21 attacks.

- REUTERS