Relatives and friends of some of the abducted Nigerian schoolgirls have identified them from a video released by Boko Haram militants, BBC reported Tuesday.
The footage showed about 130 of more than 200 girls who were kidnapped last month from their boarding school in Borno state.
Boko Haram leader Abubakar Shekau said the captured girls who have not converted to Islam can be swapped for jailed fighters.
Nigeria's government, however, said it was considering all options.
Meanwhile, the US has revealed it was flying manned surveillance missions over Nigeria to find the missing schoolgirls.
A team of about 30 US experts was in Nigeria to help with the search.
Britain, France and China also have teams on the ground in Nigeria and an Israeli counter-terrorism team was on its way, the report said.
The 27-minute footage was shown to some people in Chibok, the town from where the girls were kidnapped, Monday.
School friends and relatives identified some of the girls in the video, the report said.
The kidnapping has triggered a huge international outrage and a campaign for their release.
