It has been business as usual for many people in London, as they faced using public transport for the first time since Thursday’s attacks. Britain has been put on the highest-ever state of terrorist alert with senior police officers warning that the cell responsible for the bombing could be planning further strikes. Nevertheless, commuters on Monday seemed determined to continue as before. “If anything happens, it happens,” said one traveller. “You can’t do anything about it. I don’t want anything to happen, but it does.”Another passenger said: “I am worried about myself reaching the office as well as my colleagues – the same fear is there. On the Tube, everyone is watching each other suspiciously.” London’s Mayor Ken Livingstone always travels to work on the Underground. On Monday morning, he was among the first people to use the Tube as he encouraged commuters to return to their routines. A book of condolence for victims has been opened at London’s City Hall.