British police were questioning 11 suspects Sunday in their investigation into failed bomb attacks on London's transport system as Italian authorities worked on extradition proceedings for a further suspect.

Police believe they have captured all four men they were hunting over the July 21 botched bombings on three underground trains and a bus, which came exactly 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 Britain and the fourth in Rome.

Italian authorities started preliminary extradition proceedings on Saturday against Osman Hussain, arrested in Rome on Friday.

Britain's junior Interior Minister Hazel Blears told Sky TV: "Where people are fomenting terrorism in this country we are going to take action. We will pursue people intensively to make sure they come to justice."

The British Government is working on new anti-terrorism laws.

Police say they are still looking for anyone who may have helped the bombers and have a total of 11 suspects in custody.

Fresh attack?

British media reported fears of a fresh attack on London and said police and security forces were trying to track down a possible command structure behind the bombers.

The Sunday Times, citing security sources, reported that a third cell of Muslim militants was planning multiple suicide bomb attacks on "soft" targets in central London.

Security experts described the pyramid structure of al-Qaida to other newspapers.

"If you see the two groups of bombers as two separate teams of foot soldiers on the very bottom, then there is a possibility they are linked by the command structure in the level above," a security source told The Observer.

"This is the level we are trying to identify and track down," the source said.

The News of the World reported that it had handed fake passports and forged documents to the police which it said it found in a bag near Heathrow airport. The paper said the haul pointed to the existence of further cells.

"The documents are now being assessed by detectives from the anti-terrorist branch," said a police spokesman.

A Zambian intelligence source said in Lusaka on Saturday the authorities had signed a deportation order for suspected British militant Haroon Rashid Aswad, who would be handed over to Britain once formalities were completed.

British police say they would like to question him but say he is not a priority in the investigation into the London bombings.

The British Government is treading carefully to ensure it does not antagonize the country's Muslim communities. Ministers are launching a series of meetings over the coming months with community leaders to try to tackle the roots of Muslim radicalism.

Source: China Daily