A joint team of the army and police personnel were conducting search operation at Amjhora area last night when they were fired upon by the militants.
An encounter followed in which a civilian was killed and the two army personnel were critically injured, they said.
The militants, however, managed to escape.
The injured personnel were identified as Mahesh Kumar, a subedar and Dinesh Kumar, a sepoy, the sources said.
They were admitted to Coochbehar Civil Hospital in West Bengal.