The Bodo extremists were killed during an operation in the forest areas of Raimati under Runikhata police station around 4.45 AM in a joint operation by police and 18 Mahar Regiment, CRPF's Cobra regiment, IGP L R Bishnoi told PTI.
The organisation's self-styled military secretary and Irakdao 'brigade commander' Rwikha alias Rajiv Champagayary was among those killed.
Rwikha, accused in various cases of killings, kidnappings, extortion and other subversive activities, carried a cash reward of Rs 10 lakh.
Besides the top leader, Bengtol 'section commander' Rojong alias Roslin Mushahary, Chirang 'platoon second-in-charge' Raidwng, Rwikha's bodyguard Debanand Islary and cadre Fwrmai were also killed, the IGP said.
Rojong carried an award of Rs five lakh.