At least 15 persons were injured and two of them seriously, in a grenade blast on Sunday night (July 28) at the busy Paltan Bazar area near the railway station in Guwahati, the fifth such incident in the state in a week. The blast, suspected to be a handiwork of the banned ULFA, took place when police was checking vehicles near the station at G S Road. The injured include two police home guard personnel. "The blast took place at 7:55 PM near the Paltan Bazar police station, which is next to the railway station... We have to investigate who did this, but inputs say it is ULFA," Kamrup (Metro) Deputy Commissioner Ashutosh Agnihotri told reporters on the spot.