Will Nigeria's divided Boko Haram be more or less dangerous?
Nigerian Islamist militant group Boko Haram now has two rival leaders. Nigeria analyst Andrew Walker looks at whether the split will make it more or less dangerous.
His face became synonymous with terrible violence, his gravel-voiced rants of bloodcurdling ferocity were the hallmark of his group. Until this week Abubakar Shekau was the acknowledged leader of the Islamist insurgency in north-east Nigeria.
Now his position has been usurped by a softly-spoken man whose only propaganda video appearance to date was faceless, obscured behind a blob of digital blur.
It seems Shekau and new leader Abu Musab al-Barnawi could not be more different men, and reports about the new leader of the Islamic State group's West Africa Province indicate these are not just a matter of presentation.
It is as yet unclear which leader presents the more terrifying prospect for the future of the Islamist movement known colloquially as Boko Haram, meaning "Western education is forbidden" in the Hausa language.
The split between the Shekau and al-Barnawi factions is about the degree of ferocity with which the group has pursued its bloody campaign.
Shekau, a former lieutenant of the movement's founder Mohammed Yusuf, is absolute in his approach.
According to Shekau, everyone who refuses to submit to the group is an unbeliever, deserving of death. This includes Muslims, who have frequently been targets in the north-east, sometimes even as they prayed.
As their fight picked up momentum under Shekau's leadership, Boko Haram opened its doors to a wide array of brutally violent people.
Stories of forced cannibalism and blood ritual taking place in Boko Haram camps have been widespread in recent years.
These stories have clearly reached the ears of the Islamic State, which is led by Salafists who seek to return life to the way it was in the community of the Prophet Muhammad. Such actions are repellent even to those with a taste for brutal public atrocities.
In his interview in the Islamic State's Arabic-language magazine al-Nabaa, al-Barnawi said that there should be no more attacks on mosques, that the real unbelievers and polytheists should be the targets of future attacks.
Infighting among the group had been long expected. Even after its pledge of allegiance to the so-called Islamic State in 2015, it was hoped infighting would be an indication the group's powers were waning.
Even legitimate multinational corporations have trouble keeping their Nigerian operations in line.
They often struggle with the factors that have spelled doom for Nigeria's institutions in the past; derailed by an ingrained tendency toward ethnic chauvinism and the predisposition of leaders to capture institutions in order to fulfil personal ambitions.
Many had hoped that, as things so often go in the wider Nigerian experience, so it will also prove inside the Islamic State's West African outfit.
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
- Group split after rival leaders emerge
But al-Barnawi has deep local connections. Barnawi is a pseudonym meaning "from Borno", the state that has always been at the heart of the war.
He has what could be a crucial advantage over Shekau in his tussle to grab hold of the reins of the insurgency and putting it back on the offensive.
Al-Barnawi is the son of Mohammed Yusuf, the founder of the movement, according to Ahmad Salkida the journalist who first wrote about the group.
This has been backed up by another Nigerian security blogger, Fulan Nasrullah, who cites his own sources within the group.
Yusuf still has a cache of support, long after his killing by police in 2009, and his direct connection to al-Barnawi means his appointment is a shrewd manoeuvre.
Nigeria's government has claimed victory over the group several times and sees this leadership dispute as a sign of desperation.
But Western leaders are unlikely to take seriously any assertion that this is the last gasp of a dying insurgency.
In choosing one of Yusuf's sons, the Islamic State has shown they understand the importance of continuity of a local vision to their allies.
Concern will intensify that al-Barnawi and his IS backers will take a more international, outward-looking path.
With airstrikes on IS in Libya and pressure on them in Syria and Iraq continuing, the question remains as to what material support IS will give al-Barnawi, beyond space in their magazine.
Even a small band of die-hards can cause great carnage, and their capability to reach Western targets is likely to be strenuously re-examined.
Andrew Walker is the author of Eat the Heart of the Infidel, about the Boko Haram insurgency in north-east Nigeria