There was no immediate claim of responsibility. Islamist group al Shabaab carries out frequent bombings in their bid to topple the western-backed government.
The bomb had been placed at Mogadishu’s Benadir junction, police officer major Abdullahi Hussein told Reuters.
“The bomb ... injured seven pedestrians. There were no vehicles passing there by that time,” he said.
The injured were taken to hospital, said Abdikadir Abdirahman, director of Amin Ambulances emergency service that transported them.
Somalia has been engulfed by violence and lawlessness since the toppling of dictator Mohamed Siad Barre in early 1990s. Al Shabaab wants to install its own government based on its strict interpretation of Islamic law.
The group’s campaign of violence typically targets the military and African Union-mandated peace keeping force AMISOM although the militants are also accused of targeting civilians, something they deny.
On Sunday, four civilians died in Mogadishu in mortar attacks that were claimed by al Shabaab.
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