At least 19 people, among them suspected Islamist militants, were killed in an attempted prison break in the Somalian capital of Mogadishu, authorities said on Tuesday.

Fifteen prisoners and four guards died in the incident on Monday at the central prison, according to Abdiqani Mohamed Qalaf, a prison spokesman on state TV.

This was a rise from the eight people initially announced dead on Monday.

Some of those involved are suspected to be al-Shabaab members, and one militant escaped alive, Qalaf said.

The militants took small arms from prison guards and started shooting randomly at the policemen in and around the prison, police said on Monday.

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They were able to capture parts of the prison, and it took security forces nearly two hours to end the siege, police officer Ali Hassan Kulmiye said.

Police have said an investigation is under way.

The terrorist militia al-Shabaab has been fighting for supremacy in the poor country in the Horn of Africa for years.

The Islamist fundamentalists control large parts of the south and centre of the country and repeatedly carry out attacks.

Somalia’s government is supported by the US military, which launches airstrikes, and an African Union (AU) force.