21 of Nigeria's Chibok schoolgirls released by Boko Haram

Twenty-one of the Chibok schoolgirls kidnapped by Boko Haram more than two years ago were freed Thursday in a swap for detained leaders of the Islamic extremist group the first release since nearly 300 girls were taken captive in a case that provoked international outrage.

The freed girls, some carrying babies, were released before dawn and placed in the custody of the Department of State Services, Nigeria's secret intelligence agency.

In photos released by the government, the former captives, most now young women, appeared gaunt and exhausted. The government "wants the girls to have some rest," said presidential spokesman Garba Shehu, adding that "all of them are very tired."

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Some 197 captives remain missing, though some reportedly have died.

"We are extremely delighted and grateful," said the Bring Back Our Girls movement, which campaigned in Nigeria and internationally for the release of the girls, most of whom were teenagers when they were seized in April 2014 from their school in the northeastern town of Chibok.

"We thank the federal government and, like Oliver Twist, we ask for more," said Hauwa Biu, an activist in Maiduguri, the capital of northeastern Borno state and the birthplace of Boko Haram.

The release was negotiated between the government and Boko Haram, with the International Committee of the Red Cross and the Swiss government acting as intermediaries, Shehu said.

He said negotiations would continue for the release of the other students.

Many of the girls freed Thursday were carrying babies, said an aid worker who saw them in Maiduguri, where they were taken by helicopter after their release, before being flown to the capital of Abuja. He spoke on condition of anonymity because he was not authorized to speak to the media.

The government said at least one child, a boy of about 20 months, was among those released. Many Boko Haram captives recently freed by military action have been shunned by their communities because they came home pregnant or with babies from the fighters.

Four detained Boko Haram leaders were released Wednesday night in Banki, a town on Nigeria's northeast border with Cameroon, said a military officer familiar with the talks. Just hours later, the girls were released in Banki, he said.

But Information Minister Lai Mohammed insisted there was no swap, just "a release, the product of painstaking negotiations and trust on both sides."

'The whole nation's been waiting for you'

At a news conference, he refused to say how the girls were chosen. He said they would be "debriefed" and placed in the care of doctors, psychologists, social workers and trauma experts, and their names would be released after their parents were informed.

In Abuja, Vice-President Yemi Osinbajo welcomed the freed women, telling them: "The whole nation's been waiting for you," according to a post on the official Twitter account of the Nigerian presidency.

He said the girls' parents were on their way to the Nigerian capital to be reunited with them.

In photos of the meeting released by the government, many of the women appeared malnourished, their clothes hanging loosely over their bony frames. Others freed from Boko Haram captivity by military action have said the extremists are running out of food.

A Chibok community leader, Pogu Bitrus, said one parent had called to say the government had contacted him to say his daughter was freed. "We just want all of our girls to come home," he said.

International outrage

The abduction of 276 schoolgirls from their school in Chibok and the government's failure to quickly free them caused an international outcry and brought Boko Haram, Nigeria's home-grown Islamic extremist group, to the world's attention.

In May, one of the captives, Amina Ali Nkeki, managed to escape and told her family that some of the kidnapped girls had died of illness and that others, like herself, had been married off to fighters and were pregnant or had babies.

Soon after the kidnapping, Boko Haram leader Abubakar Shekau said he would marry the girls to his fighters, saying they should be wives, not going to school.

The name Boko Haram means "Western education is forbidden," or "sinful," in Nigeria's Hausa language.

The extremists have attacked many schools and kidnapped many thousands of girls and boys during their seven-year insurgency that has killed more than 20,000 people, according to Amnesty International.

In a statement Thursday, Shehu put the death toll at more than 30,000. Some 2.6 million people have been driven from their homes by the insurgency and the United Nations has warned that tens of thousands face famine-like conditions.

Negotiations last year failed when Boko Haram demanded a ransom of $5.2 billion for the girls' freedom, according to a recently published biography of Nigerian President Muhammadu Buhari by American historian John Paden. It was not clear if any money changed hands in this swap.

Negotiations may have been complicated by a leadership struggle within Boko Haram, where the Islamic State group has named a new leader to replace Shekau, who insists he is still in charge.

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