British police were questioning 11 suspects on 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 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, Reuters reported. Meanwhile, 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.