Suicide bombers attacked the main peacekeeping base in Somalia's capital, killing at least three Somali security officers.
Captain Mohamed Hussein said one blast took place as security forces were searching cars at a checkpoint a few hundred metres from the main base of the African Union peacekeeping force, AMISOM.
Another vehicle then drove through towards the base's main gates but came under fire from peacekeepers, police officer Mohamed Ahmed said.
It exploded about 200 metres from the gate. Civilian buildings were damaged.
The powerful blasts damaged the front of the nearby Hotel Peace, though there were no immediate reports of casualties there. The burned-out shell of one of the wrecked vehicles lay outside.
Al-Shabab spokesman Sheikh Abdiasis Abu Musab said the fighters had intended to attack the hotel, as African leaders seeking a solution to Somalia's decades-long turmoil had met there last year.
The blast destroyed most of the hotel.
Witnesses said a second explosion and heavy gunfire could be heard at the checkpoint after the attack.
Suspected al-Shabaab assailants fired mortars at Mogadishu International Airport on Sunday, killing at least two people and wounding several others.
Residents in El-Qalow located near the Airport have reported hearing the sound of explosions believed to be mortar bombing, the latest in string of attacks in Somalia's capital.
Somalia's National Intelligence and Security Agency (NISA) said two attackers have been shot dead by the security forces in the area, and seized a minibus mounted in a mortar gun, along with 2 attackers alive.
A vehicle used for firing mortars on Mogadishu Airport in Wadajir district went off shortly after it was captured by the Police and no casualties reported, said a resident.
Two attacker were killed and two are being held alive during a shootout between security forces and suspected al-Shabaab militants who carried out Sunday's mortar attack, he added.
The mortar rounds struck an area, less than one kilometer north of Mogadishu's international airport.
There were no immediate reports of civilian casualties from the mortar attack. Somali Police blamed militant group al-Shabaab, which is aiming to topple the UN-backed Somalia's Federal government.