Boko Haram says some abducted Chibok girls killed in Nigerian air strikes

Some of the abducted Chibok schoolgirls have been killed in Nigerian military air strikes, according to a new video appearing to come from Boko Haram Islamic extremists, which shows one of the alleged victims pleading for authorities to release detained militants in exchange for the girls' freedom.

The video posted Sunday on Twitter shows a girl, covered in a hijab with just her face showing, identified as one of the 276 students abducted from a remote school in northeastern Nigeria in April 2014. In the video, she claims that some of her kidnapped classmates died in aerial bombardments by the Nigerian Air Force. She also said that 40 have been "married" to Islamic extremist fighters.

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The video shows a fighter warning in the Hausa language that if President Muhammadu Buhari's government battles Boko Haram with firepower, the girls won't be seen again.

"Presently, some of the girls are crippled, some are terribly sick and some of them, as I had said, died during bombardment by the Nigerian military," the fighter says, appearing before a group of more than 40 young women in hijabs, some holding babies.

"If our members in detention are not freed, let the government and parents of the Chibok girls know that they will never find these girls again," he said.

The video, cited by the SITE Intelligence Group, was posted by Ahmad Salkida, a Nigerian journalist known to have good contacts in Boko Haram. Salkida says he was given the video by the Boko Haram wing led by Abubakar Shekau, who is in a leadership battle with a lieutenant named by the Islamic State group as the new leader of what it calls its West Africa Province.

Dozens of the schoolgirls kidnapped from Chibok escaped on their own within two days of the abduction. One girl escaped this year, saying she had been led to freedom by her Boko Haram "husband." Some 218 remain missing in the mass kidnapping that shocked the world and even brought U.S. first lady Michelle Obama to participate in the #BringBackOurGirls social media campaign, promising her husband would do all in his power to help liberate them.

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In the video, the fighter says the Nigerian government has repeatedly lied to its citizens with promises to quickly free those kidnapped from Chibok Government Girls School, who now are all over 18 years old.

The government came under increased pressure from parents and the Bring Back Our Girls campaigners after the May escape of one young woman, a proof of life that they said should encourage the military and government to redouble efforts to rescue the girls. The escapee said some of the girls had died but scores remain in captivity under heavy guard.

'We are really suffering,' pleads girl in video

Sunday's video appears to be another proof of life, though it was not immediately possible to reach any of the parents or Chibok leaders to verify the identity of those filmed.

The young woman in the video, probably speaking under duress, begs for help to free them.

"Oh you, my people and our parents, you just have to please come to our rescue: We are suffering here, the aircraft has come to bombard us and killed many of us. Some are wounded. Every day we are in painand suffering, so are our babies. Some of our husbands that we married also are injured, some dead. No one cares for us.

"Please go and beg the government of Nigeria to release the members of our abductors so that they too can free us to let us come home. We are really suffering, there is no food to eat, no good water to drink here."

The video goes on to show bodies from an alleged air raid, including that of a girl whose eyes flicker open briefly.

Nigeria's Air Force has reported near-daily bombardments of Boko Haram camps and the military of increased ground assaults in which they have freed thousands of captives, though none of the Chibok girls.

Boko Haram has been forced out of most towns in the past year and has turned to assaulting remote villages and using suicide bombers to attack targets such as mosques and marketplaces.

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More than 20,000 people have been killed in the 7-year-old Islamic uprising that has spread from Nigeria to neighbouring countries and driven 2.2 million people from their homes.

Aid workers say there is a catastrophic humanitarian crisis in newly liberated but still dangerous areas where half a million people are starving and babies dying daily. There has also been a resurgence of polio in areas that had been under Boko Haram's control, as a result of the extremists' opposition to vaccinations.