At least 7 people were killed and over 30 others injured in a powerful explosion that occurred in northwest Pakistan's city of Peshawar Friday morning, according to local TV channel reports.

Security officials said that the bomb blast exploded outside the building of Pakistan's premier intelligence agency in city of Peshawar, the capital city of North West Frontier Province.

The blast was so powerful that a building was damaged. The sources fear that people may be trapped under the rubble.

According to eyewitnesses, the gunshots were fired before the blast. Local officials said that the blast could be a remote- controlled car bomb explosion.

According to the private TV Express, over 30 injured have been rushed to the nearby Lady Reading Hospital. State of emergency has been declared in all the hospitals of the city. The relief activities have been started. The ambulances soon arrived on the blast site.

Khyber Road was blocked for any sort of traffic after the blast.