A day after Saturday's grenade attack on opposition Awami League rally in the city, two more grenades were recovered from the prison campus and a toilet at Railway Hawkers Market.

At six in the morning, a sweeper first noticed a grenade lying in a sewer channel in between Cell No. 26 and Cell No. 90 in the prison house.

The jail authorities informed police about the find and army bomb experts took it away from the jail after 12 noon.

Sighting of the grenade inside the jail, a day after killing of at least 19 and injuring hundreds in a hail of grenade explosions, raised alarm and the authorities went for combing search to make sure the prison's security.

Inspector General of Prisons Brigadier General Zillur Rahman later told reporters that the grenade could have been thrown in from outside the jail or made its way in because of security lapse.

After recovery of the live grenade and its safe transfer to army, jail staff took a sigh of relief, as Dhaka Central Jail is considered a highly sensitive place that houses the largest number of convicts and under trial accused including those of Bangabandhu Murder and Jail Killing. The verdict in Jail Killing Case is billed for September 8.

Speaking on condition of anonymity, some jail officials noted that recovery of a grenade from its compound exposes the vulnerability of Dhaka Central Jail. Had the grenade exploded giving scope for hoards of convicted criminals to escape, they feared, it could have caused a serious security threat to the country as a whole.

The other grenade found in a toilet at Railway Hawkers Market was also taken away by a team of army explosive experts led by Captain Shams at around 11am yesterday.