The troopers in the (other) vehicle fired on heavily armed guerrillas who countered the CRPF men for a while before disappearing into nearby forests under cover of darkness,' Deo told IANS.

Police officials at Dantewada town said reinforcement of about 80-100 CRPF men besides a strong contingent of state police had reached the site. But a combing operation has been deferred till Monday morning as police suspect Maoists can ambush them if they sneak into forests in night.

Forces have been put on high alert in the entire Dantewada district that has witnessed a string of deadly attacks in recent years.