Guwahati/New Delhi: The Chief Recruiting Officer of militant outfit NDFB(S), who is believed to be the brain behind the December killings of Adivasis in Assam, was on Tuesday arrested along with seven others in a joint-operation by the army and the state police.

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Self-styled 2nd Lieutenant Enon Bargoyary alias Erkhang, Chief Recruiting Officer of NDFB(S), and self-styled platoon commander of Amteka area, Rinen Basumatary alias Majhi were apprehended by joint team of army troops of Red Horn Division and Assam Police along the jungles of Assam-Bhutan Border, in Chirang District.

Enon is also the militant group's Central Committee Member, army sources said.

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A senior army officer described him as number 3 in hierarchy within the militant organisation.

Enon was allegedly involved in recruiting and motivating NDFB(S) terrorists, including women cadres, and sending them to various camps outside the country, the sources said.

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"Enon was very close to outfits SS Chairman I K Songbijit, SS Army Chief G Bedai and Dy Army Chief Batha. Enon is believed to be the brain behind the killing of Adivasis on December 14 in Kokrajhar District," the sources added.

Another key NDFB(S) member apprehended is Rinen of the outfit's 20th batch trained in Bhutan, who surrendered after Operation All Clear in 2003 but rejoined the group two years back.

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Four weapons, two AK rifles and two pistols, and large quantity of ammunition was recovered from the apprehended persons, the sources said.

The army has been carrying out operations in difficult and inaccessible forested areas of Kokrajhar and Chirang Districts which has forced NDFB(S) terrorists to flee from their safe hideouts and move to more vulnerable areas, where they are being apprehended or neutralised by the security forces.