Why now? Questions raised over Nigerian schoolgirls' release may never be answered

More than two years ago, the world looked on in horror as details emerged of the Chibok schoolgirls kidnapped in Nigeria.

Some of the 276 girls managed to escape that night, but 219 disappeared at the hands and guns of Boko Haram.

The Islamist militants and the violence they inflicted across northeasternNigeria had to that point largely been ignored around the world.

But the schoolgirls' kidnapping sparked global outrage, calls for action, social media hashtags and offers of international help with intelligence and surveillance.

It was only once it became clear that there would be no dramatic, en masse rescue and reunion that global interest slowly and quietly slipped away.

Now, 21 of the Chibok schoolgirls have been released into the hands of the Nigerian security services.How and exactly where this took place isn'tyet clear.

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The Nigerian government has confirmed that it negotiated with Boko Haram.The release was brokered by the International Committee of the Red Cross and the Swiss government.

Butthere are still questions about the timing of the release, whether a ransom was paid and whether more girls could be released.

Setting a precedent?

For some of these questions, we may never get answers. The Nigerian government is unlikely to want to go into detail about any negotiations it has had with the Islamist militants, particularly with questions swirling about the precedent it may have set.

Sources have told the media that the 21 Chibok girls were swapped for four high-profile Boko Haram commanders.

However, Nigeria's information minister has denied this was the case.

But a prisoner swap has always been the demand of Boko Haram, right from the first video released of the Chibok girls after their kidnapping.

But would any such approach leave the Nigerian government and military who continue to fight Boko Haram in a more precarious position?

• Why has Nigeria failed to rescue the Chibok schoolgirls?
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Ryan Cummings, security director with Signal Risk, told CBC News it could pose more problems if there was a prisoner swap.

"They could be senior members within the group's Shura council or individuals who had important roles in the organization."

He says they could be "strategists, bombmakers or trainers and obviously there is a possibility that they could use their skillsets against the Nigerian state amid their release."

No need for a 'long game'

But there are those in Chibok who, after more than two years waiting, want to see a Boko Haram prisoner exchange, whatever the implications.

Chibok elder Ayuba Alamson Chibokbelieves it may now be the only option if they are to see the other girls alive.

"Let them send more and free all the Chibok girls and captive victims," he told CBC Newsby phone fromthe northeastern city ofMaiduguri.

"No need for playing tactics or a long game with this sort of thing. If they have freed four Boko Haram in exchange for 21, then we want the government to negotiate with them and free the number possible that they want and free these girls, all of them, for us very soon."

Questions also remain over the negotiations, including with whom the Nigerian government was talking, and if it was directly dealing with Boko Haram, what faction of the group was involved.The group has recently indicated a deep split.

Boko Haram leaderAbubakar Shekau aligned the militant group with ISIS in 2015, swearing alliegiance to them.

But more recently, ISIS denounced him as the leader of Boko Haram, saying instead that Boko Haram would be led by Abu Musab al Barnawi, son of Mohammed Yusuf,who was the originalfounder of the group.

Video rebuke

Shekau rebuked this in a video.There has also been talk of clashes between supporters of the two men.

In seven years,more than 20,000 people have died in the violence and 2.6 million people made homeless.

The United Nations children's charity UNICEF estimates that 7,000 women and children have been held by Boko Haram in recent years.

Many of those who fled the Boko Haram violence in northeast Nigeria are facing famine and UNICEF says around 50,000 children could die before the end of the year.

The release of 21 Chibok girls is a glimmer of good news for Nigerians, one that is being welcomed.

A few of the Chibok girls who escaped on the night of the attack are continuing their studies at the American University of Nigeria in Yola in Adamawa state.

Margee Ensign, the university's director, told CBC News that "our students are thrilled at their release and look forward to communicating with them soon."

She, too, hopes that once they have recovered and found some stability, the 21 girls will also return to school for the education that was so abruptly stopped with violence that night in April 2014.

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