A car bomb exploded near a hotel and restaurants in Mogadishu on Thursday, killing at least 11 people in a busy area targeted in the past by Islamist militants, rescue services said.

The afternoon explosion sent smoke billowing into the sky and destroyed two restaurants and some cars parked in the area.

A Reuters witness counted six dead bodies.

"So far, we carried 11 dead people and 16 others wounded. The death toll may rise," Abdikadir Abdirahman, director of Amin Ambulance service, told Reuters.

Police earlier gave a death toll of eight.

"The blast destroyed a restaurant and killed many who were inside and outside the restaurant. The death toll may rise," police Major Mohamed Hussein told Reuters.

There was no immediate claim of responsibility.

Al Qaeda-linked al Shabaab militants have in the past targeted the same location - the Wehliye Hotel - which is along the busy Maka al Mukaram road.

On Saturday, 15 people died in two explosions and a gunfight between al Shabaab militants and security personnel in Mogadishu.

Al Shabaab, which is trying to topple Somalia's western-backed central government, was ejected from Mogadishu in 2011 and has since been driven from most of its other strongholds.

But it remains a threat, with fighters frequently carrying out bombings in Somalia and neighbouring Kenya, whose troops form part of the African Union-mandated peacekeeping force that helps defend the central government.