By Anna Cunningham, for CBC News
Yana Galang, the mother of Rifkatu Galang, one of the schoolgirls kidnapped by Boko Haram two years ago, looks down during an interview in Lagos on April 5, 2016. (Stefan Heunis/AFP/Getty)
When 276 Nigerian girls went to school two years ago, 219 of them never came home.
The human rights group Amnesty International has called for the Nigerian government to "do all it lawfully can to bring an end to the agony of the parents of the Chibok girls and all those abducted."
M.K. Ibrahim, country director of Amnesty International Nigeria, says: "Few of us can begin to comprehend the suffering of parents who have not seen their daughters for two years."
The simple facts of what happened in the remote town of Chibok in northeast Nigeria remain astonishing, but nothing is simple about the insurgency by the Islamist militant group Boko Haram that has blighted the region since 2009, leaving more than 20,000 dead and 2.6 million homeless.
Today the sign outside what remains of the Government Girls Secondary School in Chibok has the word "girls" blanked out. The school is a shell of broken walls and empty window frames.
One chalkboard remains, indicating what was once a classroom, as the rest succumbs to nature. Dormitory bed frames gather dust in the long grass.
A short "proof of life" video has emerged and been reviewed by the Nigerian government. It shows 15 of the schoolgirls, their heads covered and wearing long Islamic headscarves.
Each is asked to identify herself and explain that they were taken from the school in Chibok. One girl says they are speaking on Dec. 25, 2015, and pointedly says they are "all well."
A slipper lies amid the rubble of the demolished dormitories of the Government Girls Secondary School in northeastern Nigeria on March 25, 2016. (Stefan Heunis/AFP/Getty)
It's the first time any of the girls have been seen since Boko Haram released a video in May 2014.
In one respect, it gives much-longed-for hope to the families of the kidnapped girls, although it comes too late for some. Sixteen fathers and two mothers have reportedly died or been killed since the abductions.
But it also leaves many questions for the Nigerian authorities — even if it shows at least some of the Chibok girls are alive.
Where are they and why have they not been rescued? Are the Nigerian authorities negotiating with Boko Haram for their release?
Africa security specialist Ryan Cummings told the CBC he believes the girls have not yet been found because "any attempt at rescuing them risks ending in a bloodbath," an outcome he says the Nigerian government cannot risk "given ongoing criticisms of their response to the insurgency."
Cummings says negotiation is the only feasible means, but he believes a stalemate remains because any talks would "likely include ransom payments and the release of detained commanders, both of which would strengthen Boko Haram's position in the conflict."
Yana Galang, the mother of Rifkatu Galang, one of the abducted Chibok girls, holds a phone with a picture of her daughter during an interview in Lagos on April 5, 2016. (Stefan Heunis/AFP/Getty)
Brokering a deal for the release of the girls in exchange for Boko Haram prisoners was ruled out by the previous government of President Goodluck Jonathan.
When current President Muhammadu Buhari took power last May, he said: "We cannot claim to have defeated Boko Haram without rescuing the Chibok girls and all other innocent persons held hostage by insurgents."
So, has the approach changed? No one in authority will give a direct answer as to whether a deal is in the cards.
Two years ago, barely a day passed without a report of a Boko Haram attack. Tactics changed after five years of hit-and-run attacks. Territory was seized, towns and villages overrun, hostages were taken. Soon, the rebels declared the creation of a so-called caliphate.
News of attacks frequently took days to filter out because of a lack of communications in the area and the fact that the region was too dangerous for independent observers, aid agencies or journalists to reach.
Witnesses often talked about how they had no protection from the military or that soldiers had fled their posts. Troops complained of a lack of weapons and even bullets. Many refused to deploy against the better-armed Boko Haram.
Lawan Zannah, father of Aisha Zannah, one of the abducted Chibok girls, reacts during an interview in Lagos on April 5, 2016. (Stefan Heunis/AFP/Getty)
International Crisis Group, a non-governmental organization that offers political and security analysis, believes the reaction to the Chibok kidnapping of former president Jonathan's administration "ranged from indifference and denial to later incompetence and deception."
The government was "crippled by corruption and mismanagement" that left it unable to "respond promptly or effectively to the incident," the group said.
The hashtag #BringBackOurGirls, launched on the back of growing public outrage in Nigeria, found supporters across the world.
But despite the international offers of assistance to find the girls, any efforts were met with the dysfunction and disarray of the Nigerian military, stymied also by patriotic pride and complex domestic identity politics.
Surveillance experts from the U.S. and U.K. were said to have located some of the missing girls and passed on their findings to the Nigerians but they failed to follow up on the intelligence.
According to a Pentagon spokesman, U.S. personnel sent to neighbouring Chad to operate surveillance drones and support were redeployed because the Nigerian military had stopped requesting their services.
The Nigerian military's record on human rights in the conflict — abuses against civilians, including arbitrary detention, torture and extra-judicial killing — limited how much Western governments could directly assist Abuja militarily.
Two years on and despite a new president who has made defeating Boko Haram his priority, plus sweeping military successes against Boko Haram, the Chibok girls are still missing.
Helping girls threatened by Boko Haram
Certainly, there is caution in Abuja to avoid the failures of the previous administration, which prematurely announced talks and even a ceasefire without clearly identifying who it was speaking to in the Boko Haram chain of command.
Earlier this month, news emerged of an even bigger kidnapping of women and children from the Borno state town of Damasak. Five hundred were taken just months after the abduction in Chibok. Yet the incident failed to win the same attention.
And hardly a day goes by without claims from the military that dozens, sometimes hundreds, of hostages have been released across the northeast.
But as the conflict has gained more scrutiny, there is awareness that Chibok is not an isolated case, even if it is a symbol for the world of the brutality of the violence.
(Anna Cunnningham is a freelance journalist based in Nigeria.)