A former prison warden and six other prison staff have been arrested in connection with a prison break that left one guard dead in north China last month.

Former warden Zhang Heping was arrested on charges of dereliction of duty, said a spokesman for Inner Mongolia Autonomous Region's procuratorate on Friday.

Another six officials and guards had been arrested and released on bail in connection with the escape of four inmates on Oct. 17, said the spokesman.

The other staff were former deputy warden Deng Jianshe, former chief of the second section Wang Jun, former deputy chief of the second section Li Gang, policemen Xu Fumeng and Liu Wenzhi and gate guard Qian Guojun.

Meanwhile, Lan Jianguo, 34, has been honored posthumously as a revolutionary martyr Friday, according to a statement from the region's Department of Civil Affairs.

Lan, deputy chief of the second section of Hohhot No. 2 Prison, fought fearlessly with the four escaping inmates and was stabbed 56 times, the statement said.

The four inmates, two facing suspended death sentences and two serving life terms, triggered a three-day manhunt involving 12,300 police officers after their escape. Three of them were captured and one was shot dead.