Karachi, Jun 23 (PTI) A powerful bomb exploded near the office of the regional police chief in Pakistan’s restive Balochistan province today, killing at least 11 people, including four policemen, and injuring 20 others. The incident occurred near Inspector General of Police Ehsan Mehboob’s office on Gulistan Road area of the provincial capital, Quetta. TV footage showed several badly damaged cars and a road littered with broken glass. Deputy Inspector General Police Abdul Razzaq Cheema told the media that the nature of the blast is yet to be determined. “We cannot say anything about the nature of the attack. Investigations are going on,” said Cheema. “Security officials had tried to stop a car near Shuhada Chowk and the blast occurred moments later; however, we are still not sure if the car was the source of the blast,” he said. Eleven persons killed in the attack. Four of those killed were police officers, while nine security officials were among the wounded, said Fareed Sumalan, a doctor at the Civil Hospital. No one has claimed responsibility for the attack. Balochistan has been facing insurgency by Baloch nationalists and Islamist militants. PTI