A video purportedly showing some girls kidnapped by Nigeria-based terror group Boko Haram is a strategy used by the group's contested leader Abubakar Shekau to show he still controls the group, a security analyst has told IBTimes UK. The footage released by Boko Haram on 14 August shows around 50 of the nearly 300 schoolgirls kidnapped by the group in 2014.

In the video, a Boko Haram militant called on the government to release militants who had been arrested in return for the release of the girls.

The video came as Boko Haram split into two factions after the group's ally, the Islamic State (Isis), appointed Abu Musab Al-Barnawi as its new leader. Abubakar Shekau, who has been leading the group since 2009, denied he had been replaced and vowed to continue his fight.

New video is a strategy

David Otto, chief executive of global security provider TGS Intelligence Consultants, believes the latest video could be a strategy used by Shekau to show he is still in power.

"This is a strategy. These girls had been spread around different cells under the control of Abubakar Shakau at the time of abduction – with the current factional split it is likely that some of them are no longer under his control. Shakau is showing desperation and signs of distress," Otto said.

He added that Shekau could also be using the video to show he goes against IS directives, that are against any form of negotiation or dialogue with the government.

Chibok mass kidnapping

The 276 girls were kidnapped as they were attending evening school in Chibok, in the restive Borno state, on 14 April 2014. Some of the girls managed to escape andone was rescued in the Sambisa forest earlier this year, but at least 218 are still missing.

Last April, Boko Haram released a video purportedly showing 15 of the Chibok girls still alive.

Although the Chibok abduction was not the first mass kidnapping carried out by the terrorists, it was the only one that attracted international outrage, led to the creation of the global movement Bring Back Our Girls (BBOG) and shone a spotlight on the deadly insurgency of Boko Haram that had previously been under-reported.

Nigeria 'on top of situation'

Following the emergence of the video, Nigeria's information minister Lai Mohammed said the government was dealing with Boko Haram's request.

"We are on top of the situation. But we are being extremely careful because the situation has been compounded by the split in the leadership of Boko Haram," he said in a statement. "We are also being guided by the need to ensure the safety of the girls," Mohammed said. ''Since this is not the first time we have been contacted over the issue, we want to be doubly sure that those we are in touch with are who they claim to be."

Who are Nigeria's Boko Haram?

Boko Haram, which has renamed itself Iswap, fights against Western influence in Nigeria and aims to impose its version of Sharia law throughout occupied territories.

The group launches attacks in Nigeria and neighbouring countries in a bid to take control of more territory. Three Nigerian states − Adamawa, Borno and Yobe − have been under a state of emergency since May 2013.

Boko Haram has killed more than 20,000 people since 2009 and was deemed the world's deadliest terror group, surpassing Islamic State in November 2015. Nigeria has also become the world's third-most terrorised country as a result of the group's violent insurgency.

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