Boko Haram

The source, who is not authorized to speak on the record about the release, told CNN the freed girls are in military custody in Banki, a town in northeast Nigeria.

They will be transferred to the capital, Abuja, where they will have medical checks and be reunited with their families.

They are believed to be among the 276 girls, ages 16 to 18, forced from their beds by Boko Haram militants in the middle of the night in April 2014. The kidnapping from a boarding school in the town of Chibok sparked global outrage and the social media movement #BringBackOurGirls.

The move comes after Human Rights Watch published a report detailing accounts by dozens of women and girls who said they were sexually abused or coerced into sex.

The women said they were raped or abused by camp leaders, vigilante group members, policemen and soldiers at camps in Borno State's capital, Maiduguri. The camps were set up to offer aid to people displaced by fighting in Nigeria's northeast.

Dozens of victims who stayed at camps for the displaced in Borno State's capital Maiduguri told Human Rights Watch they were sexually abused or coerced into sex by camp leaders, vigilante group members, policemen and soldiers. Many of the women were abandoned after becoming pregnant.

"It is bad enough that these women and girls are not getting much-needed support for the horrific trauma they suffered at the hands of Boko Haram," said Mausi Segun, senior Nigeria researcher at HRW.

Human Rights Watch (HRW) said it had spoken to 43 victims who had been raped or sexually exploited by vigilante groups and security officials.

The president has ordered an investigation into the alleged abuses.

Islamist militant group Boko Haram's insurgency has left 20,000 people dead and more than two million displaced.

Many of those forced from their homes have fled to camps around the Borno state capital, Maiduguri.

CNN reports this from two sources with direct knowledge of the negotiations.

That's because the rest -- about 114 -- have either died, been married off, or become radicalized and don't want to leave their Boko Haram kidnappers, the sources said.

Negotiations between Boko Haram and the Nigerian government over the captives are expected to resume Monday, four days after the militant group handed over 21 former Chibok schoolgirls to authorities in northeastern Nigeria.

"To the despot Nigerian government: Die with envy. I'm not dead," Shekau says in the video.

An ISIS flag is visible in the background. That terrorist organization has said it is supporting Shekau's rival, Abu Musab al-Barnawi, as the legitimate leader of the Nigerian ISIS-affiliated terrorist movement.

Amina Ali, who was held hostage by the terrorist group for more than two years, says she was married off a year into her ordeal and later had a baby girl, Safiya.

Yakubu Kabu confirmed to CNN that he saw his daughter speaking in the new video, which demands the release of Boko Haram fighters in exchange for the kidnapped girls.

The Nigerian government has said it is now "in touch" with Boko Haram and "working for the girls' release," the Federal Ministry of Information and Culture said on their official Facebook page.

"We are being extremely careful because the situation has been compounded by the split in the leadership of Boko Haram," said Alhaji Lai Mohammed, Minister of Information of Culture, according to the statement.

Some 50 girls wearing headscarves are seen behind a Boko Haram militant who demands the release of fighters in return for the release of the girls.

The group seized 276 girls from their school in the northern town of Chibok; 219 are believed to still be held.

This is the third video said to show the girls since they were captured.

The video shows the militant carrying out a staged interview with one of the girls, who calls herself Maida Yakubu and says she is from Chibok.

"This child cannot stand," says another medic as the severely malnourished boy is carried to the intensive care unit at the Gwange therapeutic feeding center on the outskirts of Maiduguri, the capital of Nigeria's Borno state.