Gunmen in Iraqi army uniforms staged a mass kidnapping on Sunday at the office of the Iraqi Red Crescent in downtown Baghdad, police said. An official of the Iraqi aid group said the assailants abducted dozens of employees and visitors, but left women behind. The official spoke on condition of anonymity because of security concerns. Police, however, said they did not know how many people were kidnapped. They said the gunmen arrived at the office in five pickup trucks.