The toll in the blast outside the railway station in Guwahati on Thursday has risen to four as one of the 11 persons injured succumbed on Friday amid suspicions that RDX was used by ULFA to trigger the bomb.
The person who died at the Mohendra Mohan Civil hospital was identified as Madhu Debnath, Additional Superintendent of Police Rajen Singh said.
The blast wiped off the family of cycle rickshaw- puller Vinay Chauhan. He and his son had died instantly after the blast while Chauhan's wife Reema died later at the hospital.
Singh said the banned outfit was suspected to have used plastic explosives for triggering the Programmable Time Device (PTD) as was evident from the nature of the blast and the debris at the site.
The PTD was planted by the ULFA in a cycle-rickshaw parked at the auto-rickshaw stand outside the station building adjacent to the army and BSF transit camps. The blast damaged several vehicles parked there.
The station on Friday witnessed an uneasy calm with the train services operating as usual.
Northeast Frontier Railway Chief Public Relations Officer T Rabha said all the train passengers and platforms were safe and the trains started plying as per schedule soon after the blast.