Chief Minister Tarun Gogoi said: "We have decided to hand over the probe to the NIA. Some people are demanding a CBI (Central Bureau of Investigation) probe over the violence. But CBI has some limitations.
"Since there is involvement of the NDFB (National Democratic Front of Bodoland) anti-talk faction militants, we have decided to hand over the probe to the NIA (National Investigation Agency)," he told reporters here.
Violence erupted in the Bodoland Territorial Areas Districts (BTAD) Thursday night when armed NDFB cadres opened indiscriminate fire in two villages, killing five people. The second attack took place in Kokrajhar district Friday that left eight people, including children, dead.
Home Commissioner G.D. Tripathy told IANS: "Today (Saturday) morning, seven bodies were recovered from Salbari area in Baksa district."
"Armed assailants belonging to the NDFB anti-talk faction attacked two villages in Salbari area near the Manas National Park. Seven bodies have been recovered Friday night, seven more were recovered today (Saturday) morning," he said.
The violence has also led to people abandoning their homes and taking shelter in relief camps set up by district administrations. There were also reports that the militants had torched several homes.
The chief minister said the situation has improved slightly in Kokrajhar and Baksa districts Saturday and there were no fresh incidents of violence.
He said the state government has been doing its best to secure the lives of civilians in Kokrajhar and Baksa districts. Gogoi cancelled his scheduled visit to Germany following the violence.
Assam's additional director general of police (Law and Order) AP Raut Saturday said curfew was relaxed for a few hours in Kokrajhar and Chirang districts. However, the indefinite curfew continued in worst-hit Baksa district.
Police have arrested 22 people for their role in the violence, he said.
"There have been adequate deployment (of security forces) and the army carried out a flag march for the second day today (Saturday) in the affected areas...," Raut said.
Three companies of central paramilitary forces have already been deployed in each of the violence-hit districts. "More forces are coming and they would be deployed soon," he said.
There were conflicting views on what led to the violence.
Police suspect the attacks were in retaliation for the ongoing anti-insurgency operation by the security forces in the BTAD region, where some NDFB militants have been killed recently.
However, media reports Saturday said the violence could be linked to the voting pattern in the general election.
Protesting against the attacks, a mob Saturday burnt down two camps of the state forest department in Baksa's Gobardhana area. The forest guards had to fire blanks to control the situation.