The Islamic State (IS) militant group has announced that its West African affiliate Boko Haram has a new leader.

Abu Musab al-Barnawi, who was previously spokesman for the Nigerian-based Islamists, is featured in the latest issue of an IS magazine.

It makes no reference to Abubakar Shekau, Boko Haram’s leader since 2009.

He was last heard from in an audio message last August, saying he was alive and had not been replaced – an IS video released in April said the same.

Boko Haram, which has lost most of the territory it controlled 18 months ago, is fighting to overthrow Nigeria’s government.

Its seven-year insurgency has left 20,000 people dead, mainly in the country’s north-east.

Mr Shekau took over as the group’s leader after its founder, Muhammad Yusuf, died in Nigerian police custody in July 2009.

Under his leadership Boko Haram became more radical, carried out more killings and swore allegiance to IS in March 2015.

In numerous videos, Mr Shekau taunted the Nigerian authorities, celebrating the group’s violent acts including the abduction of the more than 200 Chibok schoolgirls in April 2014.

Nigeria’s army has claimed to have killed him on several occasions.

Boko Haram at a glance:

Founded in 2002, initially focused on opposing Western-style education – Boko Haram means “Western education is forbidden” in the Hausa language

Launched military operations in 2009

Thousands killed, mostly in north-eastern Nigeria, hundreds abducted, including at least 200 schoolgirls

Joined so-called Islamic State, calls itself IS’s “West African province”

Seized large area in north-east, where it declared caliphate

Regional force has retaken most territory last year

Source: BBC