Police said Saturday there would be no letup in their massive anti-terrorist operation despite the capture of the four men suspected of trying to bomb London's transit system, AP reported. Scotland Yard police headquarters appealed to the public to remain vigilant, fearing further terrorist cells could be planning an attack. Detectives were questioning the three men captured in England, hoping to learn who recruited and supported the July 7 and July 21 bombers, and how many others could still be out there. Police also were investigating how the fourth suspected bomber, Osman Hussain, managed to slip out of Britain five days after the failed attacks, despite a huge manhunt. His photograph had been issued to officials at all ports and airports, but the image of Hussain was grainy and difficult to make out, and his face was shielded by a dark baseball cap. A day after his escape, Metropolitan Police put out a second, much clearer, image of him. Italy's Interior Minister Giuseppe Pisanu said Saturday in Rome that Hussain left London's Waterloo station by train July 26. London Waterloo International is the terminal for the Eurostar, which transports passengers from Britain to mainland Europe. Hussain, an Ethiopian-born British national, was arrested in Rome on Friday, reportedly after police traced his cell phone calls. Britain has asked Italian authorities to extradite him. Security officials at Rome's Regina Coeli prison said Saturday the suspect was being interrogated by anti-terrorism prosecutors.
