There was no immediate claim of responsibility for the blast, which happened near buildings housing government offices.
Abdikadir Abdirahman, head of Aamin ambulance services, told Reuters that three of those wounded were women.
There was no immediate comment from the police.
At least 90 people were killed in Mogadishu last week in a bomb attack by Islamist militant group al Shabaab, the deadliest in the country in more than two years.
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