Security forces in Somalia have arrested a former al-Shabab commander who is set to contest in regional elections, reports from the country say.

Mukhtar Robow is one of the leading candidates seeking the presidency of Somalia’s South West state in next week’s vote.

The arrest took place amid clashes between gunmen and security forces in the town of Baidoa. So far it is not clear why Mr Robow was seized.

Mr Robow was arrested on Thursday morning as heavy gunfire was heard in Baidoa. Telecommunication lines in the town have since been cut off.

In October, Somalia’s federal government banned the former al-Shabab spokesman, who once served as the group's deputy leader, from contesting in the state elections but the electoral commission ignored the decision and gave him the go-ahead.

Mr Robow has been a major threat to the influence of Somalia's federal government in the south-west.

This latest incident will only increase his popularity, and fuel local resentment towards the government and its foreign allies.

Mr Robow divides opinion in Somalia - with some seeing him as a major resource in the fight against al-Shabab, while others still view him with suspicion because of his past as a founding member of the jihadist group.