Police say at least three Somali security officers have been killed.
One bomber drove a car into a checkpoint outside the headquarters of the African Union peacekeeping force, AMISOM.
Another vehicle then drove towards the base’s main gates, before coming under fire from peacekeepers stationed there.
Has anyone admitted the attack?
Al Shabaab militants say they carried out the assault near Mogadishu’s main airport.
The area is home to several embassies, aid groups and telecoms companies.
The front of the nearby Hotel Peace was damaged in the attack, although there are no reports of any casualties.
Al Shabaab’s military spokesman Sheikh Abdiasis Abu Musab said fighters had meant to attack the hotel.
African leaders seeking a solution to Somalia’s decades-long turmoil met there last year.