The death toll in the powerful blast following a rally in Pakistan's port city Karachi has gone up to four, a media report said Wednesday, the day after the explosion.
The blast, in which 42 people were injured, took place after a rally, under the banner of the Muttahida Quami Movement party and the Tehreek-e-Minhajul Quran.
Sindh Health Minister Sagheer Ahmed confirmed the casualties.
A police official said a motorcycle, with an explosive device strapped to it, had been installed between parked buses which was detonated by a remote control later.
The explosion took place at a point where people started to converge to get on board the parked buses to return to their destinations, following the conclusion of the public meeting in Jinnah Ground.
Many buses and other vehicles were also damaged in the blast which was heard many kilometres from the venue.