On specific information, the joint police and army team launched an operation at Banipathar area under Bokajan police station and at around 1am the militants exchanged fire with the security forces inside a forest, Superintendent of Police Debojit Deuri said.
Six KPLT were neutralised in the encounter, while an army man was injured, the SP said.
Two top leaders of the underground outfit were suspected to have been killed in the encounter, the SP said, adding, the identification process was on.
The injured army man was taken to hospital, he said.
One SLR rifle, one Insas rifle, three pistols and two grenades were recovered from the slain ultras, he said.
KPLT, formed in 2010-11 by a breakaway faction of the Karbi National Liberation Front after the KLNF declared ceasefire, is active in the remote areas of Bokajan.
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