The BBC has learnt that the second-in-command of the Islamic State group in Somalia has been killed in the capital, Mogadishu.

Mahad Moallim, who is on a US sanctions list, was shot dead by gunmen who are also believed to be members of IS.

Correspondents say it is possible that the killing was related to a power struggle amongst the jihadists as the leader of the group is reported to be in poor health.

IS is thought to have between 400 and 500 fighters and is most active in the semi-autonomous region of Puntland.

The militant group, also known as Daish, is an arch rival of the jihadist group al-Shabab.