Officials said the incident occurred around noon in the Ganjoi Pahar area of the district when commandos of CRPF's elite 205th CoBRA unit were on an anti-Naxal operation.
There was a brief exchange of gunfire between Naxals and security forces after which the Maoist squad fled, they said.
A trooper of the Commando Battalion for Resolute Action (CoBRA) has been killed while two others have been injured, they said.
The martyred commando has been identified as A Deka while the injured are A K Yadav and K Kakoti.