Islamic State's chief executioner, who has beheaded more than 100 people, has been stabbed to death in an ambush in Iraq.

Nicknamed Abu Sayyaf, he was dubbed one of the terror groups scariest decapitators and was paraded in their sick videos for his huge frame.

He was also said to be leading ISIS in the Nineveh State, where he was killed by an unknown group who swarmed terrorist territory.

Abu Sayyaf, translated to mean 'father of swordsmith', is also the name for an ISIS branch in the Philippines synonymous with beheadings and kidnappings.

The executioner, who died in the al-Dasawa region in the western side of the city of Nineveh, was renowned for collecting the heads of his victims and dumping them in the same infamous hole in the region of al-Khasafa.

Muhammad Yawar, an Iraqi journalist, told ARA News: 'Abu Sayyaf was one of the scariest executioners in Nineveh. He was known for his huge body and heavy arms. He was one of the renowned faces in the ISIS propaganda videos.

'Abu Sayyaf was a reflection of the brutality of this terrorist group.'

There are varying reports of how he came to his death, with some news outlets stating he was shot by gunmen, but according to Iraqi

News, security source told Alsumaria News: 'An unknown armed group killed on Sunday the Islamic State's most famous decapitator, the so-nicknamed Abu Sayyaf.

'The armed group ambushed him at al-Dawasa region, in the western side of the city, and stabbed him several times.

'He died immediately.'

Nineveh is located on the outskirts of Mosul, where the operation continues to liberate its people from ISIS control.