The incident occurred within a few metres from the Paltan Bazaar police station and behind the boundary wall of the Guwahati railway station at around 7.40 pm.
According to the police, unidentified miscreants hurled the grenade at a CRPF picket in the busy area. The needle of suspicion was pointed at the anti-talks faction of the outlawed United Liberation Front of Assam.
Kamrup (Metro) District Deputy Commissioner A Agnihotri said one of the CRPF jawans who was injured in the explosion died after being admitted to hospital.
Meanwhile, in another incident at Dhubri town in western Assam, three persons were injured when the police opened fire to control a mob on Saturday, following tension over a theft in a temple.
The authorities have imposed indefinite curfew in Dhubri district to keep the situation under control. Night curfew has been in force in Dhubri since violence broke out in Kokrajhar and the adjoining districts in July.
Image: Police personnel at the blast site in Guwahati