Somalia's semi-autonomous state of Puntland executed 10 fighters from Islamist militant group Al Shabaab on Saturday, the region's police said in a statement.

The executions, by firing squad, in Galkayo in the state's Mudug region, followed a trial of the fighters in a military court where they were sentenced to death for involvement in assassinations and bombings in several locations in Galkayo.

Police said the executed fighters "were previously sentenced to death by the supreme court of the armed forces, after they were found to have committed murders in the city of Galkayo".

Al Qaeda-linked Al Shabaab insurgents have been fighting for nearly two decades aiming to topple Somalia's central government and establish their own rule based on the group's strict interpretation of Islamic sharia law.