More than 4,000 prisoners of Ivory Coast's largest penitentiary escaped through the sewers amid massive political violence, and are believed hiding out in a forest adjoining Abidjan, officials said Thursday. "A lot of them" are believed to have made their way into the city, where calm was taking hold again Thursday after five days of deadly violence pitting French forces against Ivory Coast's military and loyalists, a Justice Ministry official said. "The prisoners escaped through the sewage system _ they made a hole," the official said, speaking on condition of anonymity. "They left this weekend in little groups." The escapees included robbers and murderers, the official said.