Security forces on Wednesday gunned down three cadres of a Karbi militant outfit and busted their training camp in Assam's Karbi Anglong district, an official said.The incident took place near Duni Tokbi village, defence spokesman Lt. Col. Suneet Newton said.On receiving information about the presence of militants, personnel of the Indian Army's Red Horns division and Assam Police launched an operation in the area.Militants of the Karbi People's Liberation Tiger (KPLT) opened fire at the security personnel and tried to flee. However, the security forces plugged the escape routes and shot dead three of the militants, the official said.The security forces also busted a well-concealed hideout and recovered a huge cache of arms and ammunition and incriminating documents.The slain militants included a self-styled operational commander, who was also the 'Sergeant Major' of the Unified Command of KPLT, the spokesperson said.