New Delhi - At least five separatist rebels were killed in an encounter with government troops in India's north-eastern state of Assam Monday, a news report said.

The combat between rebels belonging two separatist militant outfits, the National Democratic Front of Bodoland and Muslim United Liberation Tigers of Assam and the army took place in central Sonitpur district, the PTI news agency reported quoting defence sources.

After a fierce gunbattle that lasted nearly four hours, three NDFB and two MULTA militants were killed at 1 am local time, the report said.

Arms and ammunition including pistols, grenades, explosives and detonators were recovered from the slain militants.

India's north-east, which shares borders with China, Myanmar and Bangladesh, is a volatile region where nearly 40 separatist, tribal or leftist groups are active in five states.

More than 15,000 people have lost their lives to insurgency in the region in the past decade. (dpa)