LAGOS- Manned US aircraft were flying over Nigeria today, searching for over 200 schoolgirls abducted by Boko Haram after Abuja dismissed a prisoner-swap offer from the militants. "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 US administration official said. The official declined to be named, and it was not immediately clear what kind of aircraft were being deployed, nor where they were based. Boko Haram´s leader said in a new video obtained by sources on Monday that the girls, whose abduction had sparked global outrage, would only be released if the government freed militant fighters from custody. Abubakar Shekau made the claim in a 27-minute video, which apparently showed about 130 of the teenagers who were snatched from their school in the remote NorthEastern town of Chibok nearly a month ago. The militant leader said the girls in the video had converted to Islam and all were shown in Muslim dress, reciting the first chapter of the Koran and praying at an undisclosed location. When asked if the government would reject Shekau´s suggestion, Interior Minister Abba Moro told "Of course." State Department spokeswoman Jen Psaki said US intelligence experts were "combing through every detail of the video for clues that might help ongoing efforts to secure the release of the girls." Their disappearance has triggered global outrage, in part due to a social media campaign that has won the support of high-profile figures including US First Lady Michelle Obama, Pope Francis and Pakistani schoolgirl Malala Yousafzai.