A suicide car bomb has exploded at a checkpoint near Somalia's national theatre in the capital Mogadishu, police have told Reuters news agency.
Witnesses said the explosion was followed by gunfire. The national theatre stands about 500 meters (yards) away from the presidential palace.
There was no immediate word on whether anybody else was killed or injured.
"The bomber blew up the car after police ordered him to stop at gunpoint. We are investigating," Abdikadir Hussein, a police officer, told the news agency.
The explosion also destroyed the front wall of a nearby restaurant, he added.
There was no immediate claim of responsibility for the attack but al-Shabab militants have been trying to disrupt Somalia's ongoing parliamentary elections, due to end on 29 December.
Al-Shabab also wants to drive out African Union peacekeepers, topple Somalia's Western-backed government and impose its strict version of Islam.
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