Three men who broke out of prison and killed a policeman in north China's Inner Mongolia Autonomous Region in October last year, were executed Tuesday.

Qiao Haiqiang, Dong Jiaji and Li Hongbin were put to death by lethal injection in the regional capital of Hohhot.

Li had appealed the sentence, claiming he was an accessory, but the appeal was rejected by the Intermediate People's Court in Hohhot City. The court upheld his death penalty in August.

Four prisoners broke out of the prison in Hohhot. All were serving life terms.

Police launched a three-day manhunt for the escapees involving 12,300 officers.

The fourth prisoner was shot dead while on the run.