New Delhi: The Centre is all set to declare a tribal militant group in Assam, Karbi Peoples` Liberation Tigers (KPLT), as a banned organisation following spurt in violence perpetrated by it. A decision in this effect is expected early next week, a senior Home Ministry official said Friday. The KPLT militants killed a Superintendent of Police and another policeman in Assam`s Karbi Anglong district and their bodies were found early today. The official said the outfit mostly operates in one district, Karbi Anglong. Despite having very few members as its cadre, KPLT has been unleashing a reign of terror and was involved at least 50 violent incidents in last three months, he said. At least 20 people, including policemen, were killed and several crore of rupees were extorted from businessmen, especially contractors, by the outfit, halting development works, the official said.