Sukma comes under the Maoist-infested Bastar division.
According to a top CRPF official, over 1,000 CRPF personnel from 223 and 206 Battalion were on area domination operation on Monday when Maoists laid an ambush and opened indiscriminate firing.
The official said that the gunbattle was still on till 6.15pm on Monday. However, no additional forces were sent to the spot as nearly 1000 jawans were already there and were still retaliating.
Official added that operation was going on for around four days and the party was returning when the incident took place.