A Pakistani official says police have killed at least 12 militants involved in target killings and attacks on officers in the southern city of Karachi.

Rao Anwar, a senior police official who led the raid, said police raided a house where the militants were hiding out in Pipri district, some 50 kilometers northeast of central Karachi.

Anwar said eight militants were killed during a gunbattle inside the house, while four who escaped were later killed in the Gadap area.

He said the militants belonged to Al-Qaeda in the Indian Subcontinent and the Lashkar-e Jhangvi militant group.

Anwar also said police recovered explosive material, bomb making devices, and suicide vests.

Karachi is frequently hit by religious, political, and ethnic violence. In 2013, security forces began a sweeping crackdown on militants in the city of 20 million.

Based on reporting by AFP and Dawn