The United States is flying 'manned' intelligence missions over Nigeria in an effort to locate from the sky more than 200 abducted schoolgirls, a senior U.S. official said Monday.

Washington has also shared 'commercial satellite imagery' with the Nigerian authorities in the hunt for the missing teenagers, the senior administration official said, asking to remain anonymous. Officials have given their permission for the U.S. missions to take place.

The news comes after a chilling new video was released by the extremist group Boko Harem, who have apparently forced the Christian teens to convert to Islam.

The video released by the group Monday offered the first public glimpse of what it claimed were some of the nearly 300 Nigerian schoolgirls kidnapped a month ago. The girls' plight has spurred a global movement to secure their freedom.

It is not known how many suspected Boko Haram members are detained by security forces.

Hundreds were killed last month when leader Abubakar Shekau's fighters stormed the military's main northeastern barracks in Maiduguri, the terror group's birthplace and the headquarters of a year-old military state of emergency to put down the 5-year-old Islamic uprising.

In the video, two of the girls were singled out for questioning.

'Why have you become a Muslim?' one girl, who looked to be in her early teens, was asked.

'The reason why I became a Muslim is because the path we are on is not the right path,' the girl said, nervously shifting her body from side to side, her eyes darting back and forth.

'We should enter the right path so that Allah will be happy with us,' added the girl, who said her name had been changed to Halima because she had converted from Christianity to Islam. Like the other girls, she wore a bulky gray hijab that covered her body from head to toe, revealing only her face.

A second girl, who appeared to be in her mid-teens, was asked if she or any of the others had been mistreated. No, she said, adding that they had experienced nothing 'except righteousness.'

As the girls chanted Islamic verses, some clasped their hands together in what appeared to be the Christian style of prayer before quickly turning their palms upward, as Muslim worshippers do.

The girls' families have said most of those seized April 15 from a school in the northeastern town of Chibok are Christians.