On the night of April 14, 2014, Boko Haram fighters kidnapped more than 250 schoolgirls from the town of Chibok, Nigeria.

Two years later, most of the girls are still missing. Now CNN is broadcasting a video purportedly showing more than a dozen of the girls, still alive as of December.

The "proof of life" video had been shown to negotiators and some members of the government, the news network says.

NPR's Ofeibea Quist-Arcton described the back story, and the video, for our Newscast unit:

"Two years ago, 276 students were abducted from their dorms in a nighttime raid by Boko Haram fighters. Dozens managed to escape, but 219 girls are still missing and had not been heard from since."The video, believed to have been recorded on Christmas Day last year, shows 15 girls lined up against a dirty yellow wall wearing Muslim veils and answering questions barked out by a man behind the camera."CNN talks to mothers weeping as they recognize their daughters. One cries out, 'My Saratu,' wailing as she reaches out as if to pluck her daughter from the computer screen."

You can watch the video on CNN's website.

NPR's Michele Kelemen reports for All Things Considered that a young Nigerian woman who goes by the name Saa recognized the women in the video. She was one of the 276 kidnapped two years ago, but she says she managed to jump off a truck and escape.

"When I saw the video of my classmates, 15 of them still alive, I was so touched immediately when I saw the video," she said. "I started crying. I just wish I can talk to them. I just wish they could hear me. I wish I could tell them how much we missed them."

Saa, who now attends college in the U.S. and is not using her real name to protect her family back in Nigeria, spoke in front of members of Congress who are calling for more U.S. action, Michele reports.

Last year, Saa described the kidnapping at the Geneva Summit for Human Rights and Democracy.

The kidnapping of the Chibok girls spurred a global awareness campaign in 2014. The hashtag #BringBackOurGirls went viral.

Thousands of other children have since vanished in Nigeria and surrounding countries, according to UNICEF.

Nigeria's military claims to have saved more than 11,000 hostages in just the past two months — none of them Chibok girls.

Last month, a girl on an apparent suicide attack mission in Cameroon ran for help and surrendered to authorities, saying she was one of the Chibok girls. If true, it would be the first concrete news of the missing girls' whereabouts in months.

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