Somali security forces inspect the site of a bomb blast near Makka al-Mukarama Road in Mogadishu on Saturday.

Reuters/Mogadishu

A car bomb exploded on Saturday on a busy street in the Somali capital Mogadishu, killing at least three people and wounding at least eight, a police officer said.

The number of casualties is likely to increase, police Major Nur Farah said at the scene of the blast, which was claimed by al Qaeda-linked al Shabaab militants.

"The place is busy with hotels and supermarkets. Most of the casualties are pedestrians. The casualty number is sure to rise," Farah told Reuters by phone.

Al Shabaab fighters have launched frequent attacks in Mogadishu in their bid to topple the Western-backed government, including a major assault on a hotel used by government officials and lawmakers in November, in which more than a dozen people were killed.

A Reuters reporter said the explosion on Saturday was followed by gunfire, and smoke could be seen rising from the scene. Part of a supermarket and a number of cars were destroyed.

"We were behind the blast operation. Some government officials and soldiers died and others were injured," Sheikh Abdiasis Abu Musab, an al Shabaab spokesman, told Reuters on Saturday, without giving details of the number of dead.

Mohamed Ismail, a nurse at Madina hospital, said they had received 21 wounded people, mostly civilians.

The government is battling to rebuild Somalia after more than two decades of conflict. Al Shabaab ruled much of Somalia until 2011, before being driven out of Mogadishu by African and Somali troops.

The group wants to overthrow the government and impose its own strict interpretation of Islam on Somalia. It has been driven out of other major strongholds in Somalia but continues to launch bomb and gun attacks against officials and politicians.