Agartala, Jan 5 (IANS) Despite a crackdown against Indian militants, separatist outfits of the northeast continue to go to Bangladesh for training and come back to carry out extremist and violent activities, Tripura Chief Minister Manik Sarkar said here Wednesday.

"Taking advantage of the hilly terrain, thick forests and unfenced border, the Bangladesh-trained northeast militants cross into Indian territory to carry on their violent activities," Sarkar said while addressing the silver jubilee celebrations of Tripura State Rifles.

"Terrorism in Tripura has been largely tamed. As they are getting shelter in Bangladesh and support from various external forces including Pakistan's spy agency ISI (Inter Services Intelligence), it becomes very difficult to flush out militancy completely," he said.

According to an official document, 128 civilians and security personnel were killed by Tripura militants in 200 incidents in 2004 while two security personnel were gunned down by the separatist outfits in 20 incidents in 2010. The tribal guerrillas had abducted 92 people in 2004 and 13 villagers last year.

"Terrorists are active in only four of the 66 police stations in Tripura. The state's three-decade old terrorism is now in a 'residual phase'," Director General of Police K. Saleem Ali said.

"We will flush out the entire militancy soon. To achieve this goal, we have taken some action plan including launching a satellite-based imagery system to track the movement of terrorists," he said.

The banned National Liberation Front of Tripura and the All Tripura Tiger Force have been fighting for an independent tribal homeland in Tripura and operate out of Bangladesh, which surrounds the northeastern state on three sides, authorities said.