In the video, Abubakar Shekau, the leader of the Boko Haram terrorist group, who wants to impose Islamic Shariah law on Nigeria, says he is prepared to exchange the girls for prisoners.

The video’s authenticity has not been confirmed, and it is not clear when the footage was taken.

Shekau says the girls have been converted to Islam. In the video about 100 or so girls are shown to be wearing full-length hijabs. Three of the missing girls are shown speaking on camera.

Shekau says the girls will be held until jailed Boko Haram militants are released.