The video shows militants killed in the Marawi siege in southern Philippines.
The bodies were found under a collapsed building in the war-torn city after government forces launched an all-out offensive against the Islamic State-inspired local terror group Maute to flush out militants in the city.
CNN Philippines reported that the video was obtained from military sources on Thursday.
Military sources meanwhile told the news portal Mahmud’s wife was also found dead beside him.
CNN Philippines showed the video to Marawi joint task force commander Major General Danilo Pamonag, who confirmed that one of the bodies in the clip was believed to be Mahmud.
“It looks like him,” he said.
The military first reported that the wanted Malaysian was killed on Oct 19. President Rodrigo Duterte and armed forces spokesperson Major General Restituto Padilla confirmed the terrorist’s death the very next day.
The news portal published a letter apparently written by Mahmud to his wife, Humaira, dated Aug 13, that was said to have been found among the debris.
In the letter, Mahmud expressed his love for her and told her not to worry about the baby she was pregnant with.
“Hoping and praying we will meet them in paradise again,” he wrote, ending with a drawing of a heart and a smiley.
Mahmud was known among extremist groups as Abu Handzalah.
He was in charge of recruiting fighters and was a point person for foreigners wanting to join extremist forces in the Philippines.
Mahmud was also reported to have been responsible for training and sending militants to fight in Syria and Iraq.
Among those he recruited was Malaysia’s first suicide bomber, Ahmad Tarmimi Maliki.
Mahmud was a former Islamic Studies professor at Universiti Malaya in Malaysia, who trained at an Al-Qaeda camp in Afghanistan in the late 1990s while studying in Pakistan and fled to the Philippines in 2014 when Malaysian authorities exposed him as an extremist.
On Oct 23, the Philippine government declared the five-month-long conflict in Marawi over.
Abu Sayyaf leader Isnilon Hapilon and Maute group leader Omar Maute were also killed in the onslaught.
More than 1,000 people, mostly militants, have been killed during clashes between both terror groups and troops since May 23.
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