China's Ministry of Justice (MOJ) has ordered prisons nationwide to strengthen security and supervision measures after four criminals killed a jail guard and escaped last Saturday.

All prisons should conduct a thorough overhaul of the security facilities and measures to comb out defects in equipment and procedures as soon as possible, the ministry said in a statement issued on Wednesday.

The priorities should be focused on safety controls and emergency management and every staff member of the prisons, from wardens to guards, should shoulder their due responsibilities for the security, the statement said.

The four prisoners killed a jail guard, using his card and finger prints to breach the No. 2 Prison in Hohhot, capital of north China's Inner Mongolia Autonomous Region.

One was shot dead and the other three were captured alive in a county near Hohhot on Tuesday after nearly three days of manhunt by more than 10,000 policemen and armed policemen in the region.