Suicide car bombing in Somalia's capital wounds at least 4

A Somali police officer says at least four people are wounded after a suicide bomber detonated an explosives-laden vehicle outside the compound of a district headquarters in Somalia's capital.

Capt Mohamed Hussein says the bomber tried to speed through a checkpoint but was stopped by security forces, prompting him to detonate the vehicle near the gate of Howlwadag district headquarters.

He says the wounded are mostly young students at a nearby Islamic school.

Officials warn there could be more casualties as the blast pulled down nearby buildings including a mosque.

There is no immediate claim of responsibility for the explosion, which shattered a period of calm in seaside Mogadishu.

The al-Shabab extremist group often targets the capital.