Somalia's Puntland region executes 21 al-Shabab fighters

The Somali government has been fighting al-Shabab for more than a decade

Twenty-one men have been executed in Somalia's semi-autonomous state of Puntland after they were convicted of being members of the Islamist militant group al-Shabab.

They were sentenced by a military court in Galkayo and shot by a firing squad.

State radio said 18 of the men had carried out assassinations and bombings over more than a decade.

As they were being executed the group attacked a town in another part of Somalia, reportedly killing soldiers.

Similar death sentences have been handed down by courts in other parts of Somalia before.

But this is reported to be the largest number of executions of al-Shabab members ever in Puntland.

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The authorities in Puntland had vowed to bring to justice any members of al-Shabab or people found assisting the group in its attacks.

The BBC's Africa editor Will Ross says the Islamist group still poses a huge threat to Somalia's stability.

Al-Shabab controls much of the country's southern and central parts, and research published in October by the Hiraal Institute said the militants raised more cash than the Somali government.

As the executions were being carried out on Sunday, al-Shabab fighters stormed the town of Wisil in the Mudug region.

There are some reports that at least 20 soldiers were killed when an army base was attacked.