At least 10 underground cadres have been killed and several injured in a fierce gun battle between the Issac-Muivah and the Khaplang factions of the National Socialist Council of Nagalim in Manipur's Tamenglong district since Wednesday, reports said.

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Which group has suffered the casualties is not yet clear.

At least 800 villagers of Ajioram area have fled their houses as the two groups fought a pitched battle. The NSCN-K is being helped by the cadres of the Manipur Peoples Army, a bitter rival of  NSCN (IM), sources said.

It is not yet clear whether the Indian Army or Assam Rifles has rushed to the scene, although NSCN-K spokesman K Mulatonu, in a message to this reporter, claimed that the NSCN (IM), which is currently in a negotiation mode with the Government of India, is being reinforced by Indian Army troops.

The fighting between the two rivals is the latest in a series of clashes that have been taking place for the past fortnight. It comes on the eve of the landmark visit of the two top leaders of the NSCN (IM) -- Issac Chisi Swu and Thuingaleng
Muivah -- to Nagaland scheduled for next week.

The duo is currently in Delhi holding talks with top Indian political leaders, including Sonia Gandhi, Prime Minister Manmohan Singh, former PM Atal Behari Vajpayee and Home Minister Shivraj Patil.

They are expected in Dimapur, Nagaland's commercial hub, some time next week and are likely to spend up to a month confabulating with various groups and members of the civil society.