Acting on specific information about the presence of a group of ULFA militants who have come down from neighbouring Meghalaya, the police launched an operation in Parabari village under Boko police station area.
An encounter followed as the militants opened fire, Kamrup (Rural) Superintendent of Police Parthasarathi Mahanta said.
A militant was killed in the encounter while the others managed to escape, he said.
A pistol, three rounds of ammunition and two empty cartridge shells, two bags with dress materials and some documents have been recovered from the slain militant who was yet to be identified.