Boko Haram has released a new video purportedly showing some of the schoolgirls kidnapped by the jihadist group from the Nigerian town of Chibok more than two years ago.

Key points: 276 schoolgirls were kidnapped from Chibok in April 2014

276 schoolgirls were kidnapped from Chibok in April 2014 Man in video says children still in group's hands

Man in video says children still in group's hands Says some have died from "aerial bombardment"

The footage was issued just days after embattled Boko Haram leader Abubakar Shekau denied claims he had been replaced as the leader of the Nigeria-based group.

The kidnapping of 276 schoolgirls from Chibok in April 2014 provoked global outrage and brought unprecedented attention to Boko Haram and its bloody quest to create a fundamentalist state in northeastern Nigeria.

While Nigerian President Muhammadu Buhari has said that the group is "technically defeated", his Government has struggled to find the girls — a political embarrassment for the leadership highlighting Boko Haram's continued presence in the region.

"They should know that their children are still in our hands," said an unidentifiable man in the video posted on YouTube.

It was attributed to the old Boko Haram name, not the new Islamic State West Africa Province (ISWAP), suggesting it was released by Shekau's faction.

"There is a number of the girls, about 40 of them, that have been married," said the man in the 11-minute video, which shows girls with veils sitting on the ground and standing in the background.

"Some of them have died as a result of aerial bombardment."

The man called on the Nigerian Government to release Boko Haram fighters in exchange for the girls.

Nigeria's Information Minister Lai Mohammed said in a statement the Government "was on top of the situation" to free the girls.

"Since this is not the first time we have been contacted over the issue, we want to be doubly sure that those we are in touch with are who they claim to be," he said.

'We're certain that these are the Chibok girls'

The father of one of the schoolgirls said he recognised his daughter in the video.

"When I heard her voice, I realised she is my daughter," Kanu Yakubu said.

He was referring to Maida Yakubu, whom he identified as the girl seen in the video choking back her tears as she described an air strike by the Nigerian armed forces.

The girl speaks in the Chibok dialect.

Bring Back Our Girls spokesman Abubakar Abdullahi earlier on Sunday said at least one of the girls had been recognised by a member of the movement.

The girls were kidnapped more than two years ago. ( AFP: Boko Haram )

The number of girls identified from the video has now risen significantly, he said.

"We're certain that these are the Chibok girls," he said.

"We recognise up to 10 from the video."

He said the group is waiting for confirmation from the Nigerian Government and parents of the girls before releasing any more names.

'Bargaining chips'

Last week, Shekau appeared in a video vowing to fight on, amid a leadership scuffle between him and new Islamic State-backed rival Abu Musab al-Barnawi.

Barnawi has criticised Shekau's indiscriminate and brutal leadership in Nigeria that has seen Boko Haram fighters kill thousands of people in mosques and markets and raze entire cities to the ground.

"This focuses on using the girls as a bargaining chip," said Ryan Cummings, director at intelligence firm Signal Risk.

"The video shows that the war effort is hurting the operations of the group.

"It does have a sense of almost desperation from Boko Haram."

Boko Haram has been blamed for some 20,000 deaths and for displacing more than 2.6 million people since it launched a brutal insurgency in Nigeria in 2009.

AFP