The United States was Monday flying "manned" missions over Nigeria to track down more than 200 abducted schoolgirls as experts pored over a new video seeking clues to where they are being held.
"We have shared commercial satellite imagery with the Nigerians and are flying manned ISR (intelligence, surveillance and reconnaissance) assets over Nigeria with the government's permission," a senior administration official said, asking not to be named.
It was not immediately clear what kinds of aircraft were being deployed, nor where they had come from.
But a new video released by the Boko Haram group purportedly showing about 130 of the girls was being carefully studied by American experts in the hope it might yield vital clues as to where they are being held.
"Our intelligence experts are combing through every detail of the video for clues that might help ongoing efforts to secure the release of the girls," State Department spokeswoman Jen Psaki said earlier Monday.
"We have no reason to question its authenticity," she added of the video.
In the video, the Islamic militant group's leader Abubakar Shekau said the girls may be released once Nigeria frees all the Boko Haram prisoners it has in custody.
But that proposal has been rejected by the Nigerian government, and Psaki recalled that the US policy is also "to deny kidnappers the benefits of their criminal acts, including ransoms or concessions."