At least six people were injured in a blast which occurred in Karachi's Gulistan-i-Jauhar area late on Saturday night, DawnNewsTV reported.
The blast reportedly targeted a Mehfil-i-Milad being held near the Perfume Chowk in Block 18 area of the neighbourhood. SSP East Azfar Mahesar told Dawn that unidentified attackers riding a motorcycle reportedly hurled a homemade grenade near the venue and fled.
Following the blast, police and rescue teams rushed to the site and shifted the injured to a nearby hospital where the condition of two was said to be critical who were later shifted to Jinnah hospital.
IT Minister Khalid Maqbool Siddiqui and MQM leader Khawaja Izharul Hasan were present at the event at the time of the blast but remained unhurt.
Police, however, mentioned that the gathering was arranged without taking prior permission from relevant authorities.
Soon after the incident, Sindh Chief Minister Murad Ali Shah telephoned Khawaja Izhar and Faisal Subzwari and inquired about the incident.
Khawaja Izhar informed the chief minister that his driver and Khalid Maqbool's coordinator were among those injured in the attack.
Meanwhile, Sindh IG Kaleem Imam has sought a report from the SSP East.
There has been no immediate claim of responsibility from any group.
Last month, two teenagers were killed while eight others injured in an explosion in Quaidabad area of the metropolis.