Karachi, May 31: A small bomb ripped through a passenger bus in Pakistan's southern Sindh province today, injuring at least four people, authorities said. No one immediately took responsibility for the explosion in Hyderabad, some 100 kms north of the port city of Karachi.
It was the second such attack in the city in recent weeks, paramilitary ranger official Lt Col Ghazanfar Abbas Shah said.
The homemade device, attached to a timer and planted under a seat, exploded when the bus was about to depart for Mirpur Khas, 250 km northeast of Karachi, Shah said.

He said that it was too early to say who was behind the explosion.
"We have ordered an inquiry,'' he said.

In recent years, many parts of Sindh province have experienced explosions and other attacks blamed on ethnic and religious rivalries.
The most recent bus bombing occurred in Hyderabad on May 10, injuring six passengers.
Bureau Report