An insurgent accused of masterminding a bloody Baghdad church siege last year grabbed a policeman\'s gun mid-interrogation and led a prison mutiny that left four Iraqi police, including a general, and 10 detainees dead, officials said Sunday. The incident came as security was tightened in Iraq where authorities fear reprisals from the local branch of Al-Qaeda after the death of Osama bin Laden in a US special forces raid in Pakistan on Sunday, with 24 policemen already having been killed in a car bomb south of Baghdad on Thursday. Among those killed in the prison was police Brigadier General Moayed al-Saleh, the head of counter-terrorism for Baghdad\'s central Karrada district, a lieutenant colonel, and a first lieutenant, a senior counter-terrorism official said, speaking on condition of anonymity. An interior ministry official, who did not want to be named, confirmed the police death toll.