war activists say they plan to hold a protest when Tony Blair arrives to sign copies of his autobiography, “A Journey,” in central London next month. Stop The War Coalition says they will picket the event and warn that activists will try to arrest the former prime minister for alleged war crimes. Security is expected to be tight at Waterstone's in Piccadilly, the six-floor bookstore that is one of the largest in Europe. Customers have been told they cannot take their mobile phones into the venue and no one is allowed to take photographs of Blair. Blair remains a controversial figure in Britain, where many remain angry at his decision to take the country into Iraq and what some said was a too-close relationship with former US President George W. Bush.