At least 15 others, including Justice Maqbool Baqar, were injured in the blast.
"According to initial information, seven people have been killed," Sindh Information Minister Sharjeel Memon told Dawn News.
Five policemen, one paramilitary Ranger and Baqar's driver were killed in the blast, reports said.
The bomb was planted in a motorbike and it was detonated by using a remote control, the police said.
A bike, a car, a police van and nearby buildings were damaged in the blast.
Baqar has been hospitalized.
Security personnel have reached the spot and cordoned off the area.
--IBNS (Posted on 26-06-2013)