The execution-style killings of two Muslim midwives in north-eastern Nigeria have raised fears that the Islamist insurgency is far from over.
The Islamic State (IS) group and the political tensions ahead of elections in Africa’s most-populous nation are being blamed for the upsurge in violence this year.
Hauwa Liman and Saifura Ahmed Khorsa both worked for the International Committee of the Red Cross (ICRC) when they were kidnapped along with another female aid worker from the town of Rann in March.
Fighters from a Boko Haram faction loyal to IS – known as the Islamic State West Africa Province (Iswap) – were behind their abduction.
Ms Khorsa, 25, was shot dead in September and a month later Ms Liman, her 24-year-old colleague, was also murdered.
Local journalists who have seen the two videos released by the jihadists after the killings say the women, wearing white hijabs, were forced to kneel down with their hands tied.
They were then shot from behind at close range.
Schoolgirl in captivity
It is not clear what demands the militants were making – but whatever they were the group says the government ignored them.
Iswap, which is believed to receive instructions from IS leadership, has raised its profile this year and was behind the kidnapping of 110 schoolgirls from the town of Dapchi in February.
Most of the girls were released after a month, except for a 15-year-old who has reportedly refused to convert to Islam and remains in captivity.
Iswap appears to be the dominant Boko Haram faction since a split in the leadership of the group emerged in August 2016.
Boko Haram launched its insurgency nearly nine years ago taking over large swathes of land in north-eastern Nigeria where it declared an Islamic caliphate.
Its leader, Abubakar Shekau, gained worldwide notoriety five years later after kidnapping more than 200 schoolgirls from Chibok.
In the wake of this, Shekau’s fighters joined IS, but it appears to have been a fractious relationship.
IS sacked him two years ago replacing him with Abu Musab al-Barnawi.
Many analysts believe Shekau – who is now rumoured to be ill – was removed because of the tactics he used, often sending child suicide bombers to launch indiscriminate attacks on civilians that included targeting places of worship.
Over the last three-and-a-half years, most areas under the militants’ control have been recaptured, though the two factions have continued to carry out attacks.
But IS’ influence is becoming more visible – and security analyst Abdullahi Yalwa believes some of Iswap’s insurgents are possibly being trained at IS camps outside the country.
Iswap has been behind several daring and deadly attacks against the military in the last four months.
They brazenly drive in convoy in gun-mounted trucks to target soldiers in an apparent attempt to acquire more weapons and armoured vehicles.
The reticent military has not commented much on the attacks, except to say they were “fierce”.
Many observers believe the authorities are cautious about revealing the actual death toll for fear of demoralising soldiers fighting the insurgents.—BBC