Maoists on Thursday opened indiscriminate fire near a camp of the Chhattisgarh Armed Force in Naraynpur district, killing four jawans and leaving another injured. Some jawans of the force were involved in their regular chores near the camp of the 16th battalion of the Force in Bharaghati village when the Maoists started firing at them, killing four jawans and leaving another injured, Additional Director General of Police Ram Niwas said.