( CNN ) -- Thirty-five Nigerian policemen are missing following an insurgent attack Saturday on a police training school in one of the most volatile parts of the African nation , police said . A search-and-rescue effort has been launched after the third attack this month the Gwoza Training camp in Borno State , according to a statement posted online by the Nigeria Police Force . It was not immediately clear whether anyone had claimed responsibility . Afterward , the force 's Inspector-General Suleiman Abba ordered that security be tightened around all police facilities in the country . It 's not known what happened to the missing officers , though the police force statement did say there is a `` very promising prospect of locating them . '' `` While enjoining all citizens to remain calm and join hands with the security forces in the collective fight against insurgency , the IGP restates his determination to work closely with other security agencies to stem the tide of terrorism in the country , '' added the police in their statement out of Abuja , Nigeria 's capital . Nigeria has been beset by violence for some time , particularly in the northeastern states of Borno , Yobe and Adamawa . Much of it has blamed on the Islamist militant group Boko Haram -- whose name means `` Western education is sin '' in the local Hausa language . The group has bombed schools , churches and mosques ; kidnapped women and children ; and assassinated politicians and religious leaders alike .
Police : Insurgents attack a police training school in Borno for the third time this year . A search - and - rescue effort is launched for the injured students . Northeast Nigeria has been beset by violence .