A vehicle filled with explosives rammed into the headquarters of Pakistan Rangers, a paramilitary force, in the southern city of Karachi Thursday morning, killing at least two officers and injuring 14 others, the Express Tribune reported.

The suicide bomber appeared to have targeted residences of the Rangers situated in North Nazimabad area of Karachi, causing extensive damage to the building in an explosion that was reportedly heard across the city.

Footages aired by the Pakistani television channels showed plumes of smoke rising into the sky.

Sindh Police chief Fayyaz Leghari said nine Pakistan Rangers, several policemen and two civilians were among the injured. According to witnesses quoted by the media, the bomber’s truck was carrying vegetables.

"We have found body parts, which suggests it was a suicide attack. A vehicle laden with explosives hit the gate of the building," Leghari was quoted as saying by India Today.

No militant group has claimed the responsibility for the attack though the Taliban and al-Qaeda were held responsible for similar attacks on security forces in the past.