Boko Haram, the Nigeria-based militant group, has purportedly released a new video claiming that some of the Chibok schoolgirls were killed during Nigerian military airstrikes.

The extremist group abducted the girls in April 2014, and most are still missing. The case spurred an international outcry and prompted the "Bring Back Our Girls" campaign.

The video "shows about 50 girls, wearing headscarves and one carrying a baby, behind a militant who's demanding the release of detained extremist fighters in return for giving the girls their freedom," as Ofeibea Quist-Arcton told our Newscast unit.

Here's more from Ofeibea:

"This is the third video to show the missing Chibok students since their mass abduction in April 2014 from their school in the remote northeastern town of Chibok. 218 are still missing. The latest video posted on Twitter also shows one veiled girl, identified as one of the 276 students captured. She says some of her classmates have been married off to Boko Haram militants. A separate scene shows bodies on the ground, suggesting they were killed in aerial bombardments by Nigeria's military."

And as The Associated Press reported, it's "not clear how many schoolgirls have died among the 218 who remain missing."

The militant group pledged allegiance to the Islamic State last year. Now, it appears to be in the middle of a leadership struggle, as we have reported: "The Islamic State has officially named Abu Musab al-Barnawi as the militant group's new leader and says he will pursue a different strategy — but the old leader, Abubakar Shekau, says he's still in charge."

James Zenn, an analyst at the Jamestown Foundation, told The New York Times that "it appears that the girls in video are in the custody of Mr. Shekau's group," citing "logos seen in the video and a references to Mr. Shekau as the leader."

This indicates that the old leader, who allegedly has tense relations with the Islamic State leadership, "has significant logistics capabilities if it has been able to keep so many of the world's most sought-after girls hidden and captive for more than two years now," as Zenn told the Times.

In May, Nigerian authorities said that one of the captive girls was found wandering in the Sambisa Forest, which Ofeibea described as "one of the main hideouts of Boko Haram."

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