Lagos, Nov 30 : At least 11 persons were killed and 252 inmates escaped from a custodial center in central Nigeria's Plateau state when a group of unknown gunmen attacked the facility, an official has said. Francis Enobore, a spokesman for the Nigerian Correctional Service (NCoS), in a statement on Monday added that one of the guards at the facility and nine inmates lost their lives during the attack on the custodial center by the gunmen in the city of Jos, the capital of the Plateau state on Sunday evening, Xinhua news agency reported. Enobore said another member of the staff was shot in the hand and six inmates were also injured in the attack. One of the gunmen was also killed in the gun duel, he added. According to the spokesperson, some attackers and 262 inmates escaped in the melee before reinforcement could come from sister services, noting that 10 inmates have so far been recaptured, leaving 252 at large. Enobore said efforts are ongoing to hunt down all "the perpetrators," and the situation has been brought under control with security further beefed up at the facility. He called for collaboration from locals to apprehend the fleeing inmates and for volunteering credible intelligence that could "nip such ugly incidents in the bud." The Jos custodial center at the time of the attack had 1,060 inmates, comprising 560 pre-trial detainees and 500 convicts, he added. The Nigerian government in October said that it had launched an audit of prison facilities in the country to determine their vulnerability, following a spate of jailbreaks in parts of the country in recent months. /IANS