A former prison warden and four other prison staff have been charged with dereliction of duty in connection with a prison break that left a policeman dead in north China's Inner Mongolia Autonomous Region in November 2009.

Zhang Heping, former head of the No. 2 Prison in Hohhot, was charged along with former chief of the second section Wang Jun, policemen Xu Fumeng and Liu Wenzhi and gate guard Qian Guojun, said a spokesman for Inner Mongolia Autonomous Region's procuratorate.

Four prisoners, two given suspended death sentences and two serving life terms, broke out of prison in the capital of north China's Inner Mongolia Autonomous Region after killing a prison policeman on Oct.17, 2009.

They triggered a three-day manhunt involving 12,300 police officers after their escape. One of them was shot dead on the spot and the other three captured.

The three were sentenced to death in August, with executions pending for approval by the Supreme People's Court.