A Boko Haram flag flutters from an abandoned command post in Gamboru deserted after Chadian troops chased them from the border town on February 4, 2015. Nigerian Boko Haram fighters went on the rampage in the Cameroonian border town of Fotokol, massacring dozens of civilians and torching a mosque before being repelled by regional forces. AFP PHOTO/STEPHANE YAS        (Photo credit should read STEPHANE YAS/AFP/Getty Images)
STEPHANE YAS/AFP/AFP/Getty Images
A Boko Haram flag flutters from an abandoned command post in Gamboru deserted after Chadian troops chased them from the border town on February 4, 2015. Nigerian Boko Haram fighters went on the rampage in the Cameroonian border town of Fotokol, massacring dozens of civilians and torching a mosque before being repelled by regional forces. AFP PHOTO/STEPHANE YAS (Photo credit should read STEPHANE YAS/AFP/Getty Images)
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Aishat Alhaji , one of the kidnapped girls from the Government Girls Science and Technical College Dapchi who was freed, is photographed after her release, in Dapchi, Nigeria, Wednesday March. 21, 2018. Witnesses say Boko Haram militants have returned an unknown number of the 110 girls who were abducted from their Nigeria school a month ago. (AP Photo/Jossy Ola)
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A screengrab taken on May 12, 2014, from a video of Nigerian Islamist extremist group Boko Haram obtained by AFP shows girls, wearing the full-length hijab and praying in an undisclosed rural location. Boko Haram released a new video on claiming to show the missing Nigerian schoolgirls, alleging they had converted to Islam and would not be released until all militant prisoners were freed.  A total of 276 girls were abducted on April 14 from the northeastern town of Chibok, in Borno state, which has a sizeable Christian community. Some 223 are still missing. AFP PHOTO / BOKO HARAM 
RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / BOKO HARAM" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTSHO/AFP/Getty Images
boko haram/afp/getty images
A screengrab taken on May 12, 2014, from a video of Nigerian Islamist extremist group Boko Haram obtained by AFP shows girls, wearing the full-length hijab and praying in an undisclosed rural location. Boko Haram released a new video on claiming to show the missing Nigerian schoolgirls, alleging they had converted to Islam and would not be released until all militant prisoners were freed. A total of 276 girls were abducted on April 14 from the northeastern town of Chibok, in Borno state, which has a sizeable Christian community. Some 223 are still missing. AFP PHOTO / BOKO HARAM RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / BOKO HARAM" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTSHO/AFP/Getty Images
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Story highlights

Abubakar Shekau also taunted the parents of kidnapped Chibok schoolgirls

"I'm not dead," he says in response to army reports he was fatally wounded

(CNN) —  

Boko Haram’s embattled leader, Abubakar Shekau, appears in a new video to deny reports of his death and to taunt the parents of the nearly 300 school girls the group kidnapped from their boarding school in 2014.

“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.

A Boko Haram  video shows embattled leader Abubakar Shekau
Boko Haram Propaganda/Youtube
A Boko Haram video shows embattled leader Abubakar Shekau

The video was a response to the Nigerian army’s claim that it “fatally wounded” Shekau in a raid August 19. The army dismissed the video Sunday as evidence of Shekau’s desperation.

“The video has shown beyond all reasonable doubt the earlier suspicion that the purported factional terrorists’ group leader is mentally sick and unstable,” the army statement said.

CNN cannot independently confirm when the video was shot, or confirm its claims.

The attack that brought Boko Haram international notoriety was when Shekau’s forces captured approximately 300 girls – between the ages of 16 and 18 – from a boarding school in the town of Chibok in Borno state in April 2014.

Boko Haram, which opposes western education, wants to set up an Islamic caliphate in Nigeria.

In the video, Shekau teases parents of the Chibok schoolgirls about whether their daughters will be released and insists detained Boko Haram fighters must be released for the return of the schoolgirls.

“There’s still a long way to go. There’s still more to do by Bring Back Our Girls,” says Shekau in the video.

“We don’t (bring) back your girls. If you want your girls bring back our brethren. Bring back our brethren.”

The kidnapping sparked global outrage and prompted global figures, including activist Malala Yousafzai and US first lady Michelle Obama, to support the campaign to #BringBackOurGirls.

For a year after they were taken, the abducted girls were kept together, Amina Ali, an escaped schoolgirl told CNN in August. Then some of the teenagers – including her – were “given” to the terrorists as wives.

Shekau, however, is still shrouded in mystery. A Boko Haram insider told CNN in August the group had split after new leader al-Barnawi broke with Shekau and left with some followers, a move which the insider said left Shekau with most of the fighters in the Sambisa forest and also in control of the schoolgirls, a powerful bargaining chip for the group.

The army contends Boko Haram is significantly weakened and has been “irrational and unreliable” in negotiations over the schoolgirls.

CNN’s Merieme Arif and Sarah Faidell in Atlanta; Aminu Abubakar in Kano, Nigeria; and Stephanie Busari in Lagos, Nigeria, contributed to this report.