Gunmen who fired on a bus carrying Shiite Muslim worshippers in the southern Pakistan port city of Karachi killed at least four and wounded several others.
About 20 Shiite Muslims were on their way to a mosque for Friday prayers when the attack happened, said Mr Athar Rashid Butt.
Nobody claimed responsibility, but suspicion fell immediately on one of several Sunni Muslim extremist groups that have killed hundreds of minority Shiite Muslims over recent years.