However, CRPF sources said only nine of its men were injured, three of them seriously, in the attack by the militants on National Highway 37 near Ranjuli.

The police said the militants waylaid 54 CRPF battalion personnel travelling in two vehicles to Guwahati from Goalpara to collect commodities and exchanged fire with them.

A civilian vehicle which had arrived at the scene came under heavy firing. Two of its passengers were killed on the spot and two others injured, the police said.

Senior civil, police and CRPF officials have rushed to the site, the police said, adding investigations into the incident are on.

Meanwhile, the ULFA has claimed responsibility for the killing of its former Kamrup unit assistant secretary Anjanjyoti Gogoi alias Rishiraj Sinhafor his ``anti-organisation'' activities.

Gogoi, who was expelled from the ULFA for his revolt against the outfit and in particular its leaders, was killed here on Saturday night.

The outfit's central publicity secretary Mithinga Daimary said in a facsimile message here last night that Gogoi was killed for allegedly helping the army in the recent surrender of its 200 cadres and collecting huge amounts unauthorisedly, in the name of ULFA.

He alleged Gogoi had kidnapped some ULFA activists and forced them to surrender, adding those who submitted themselves would not be regarded as enemies.

Police said two persons have been picked up in connection with Gogoi's killing.

Elsewhere in Agartala, militants kidnapped three persons, including two traders last night, while 28 others, including two central government employees, 17 bus passengers, teachers and doctors, continued to be in captivity continued to be in captivity since last week.

Police said armed militants attacked Lefunga Bazar in West Districtand abducted two businessmen, Nitai Das and Kanu Chakraborty, at gun point.

Another trader, Jiten Ghosh sustained serious injuries when he tried to resist the ultras, the police said. He had to be admitted to G B Hospital.

In a separate incident at Karaticherra in Dhalai district, National Liberation Front of Tripura (NLFT) militants stormed into the house of a villager, Brajagopal Dhar, last night and kidnapped him at gun point.