Suspected al-Qaeda militants have attacked a Yemeni intelligence headquarters in the country's southern city of Aden. They killed at least 20 people.

The militants attacked from two sides, firing rocket-propelled grenades and automatic weapons inside. Officials say one group clashed with guards at main gate. A second group threw a bomb at a small mosque, killing soldiers resting inside.

The gunmen then sprayed their victims with bullets before detonating a car bomb in front of the intelligence building. A security official speaking on condition of anonymity says the attack carries the fingerprints of al-Qaeda. The terrorist group remains active in the area.