New method, same old savagery.

The Islamic State (ISIS) has found yet another barbaric way to kill its enemies. According to Iraqi News, the terror group recently executed six of its leaders using a flamethrower—a weapon that sprays out burning fuel.

"The six ISIS leaders were executed by their counterparts using flamethrower," Iraqi News quoted Ismat Rajab, a Kurdistan Democratic Party official in Mosul, as saying. "They were executed as they tried to escape to Syria."

The execution reportedly took place in Nineveh province in northwestern Iraq.

Meanwhile, Iraqi President Fuad Masoum has apparently decided to give ISIS a dose of its own medicine. Earlier this month, he announced that his government will execute 36 convicted ISIS terrorists who were found responsible for the massacre of 1,700 people in Camp Speicher, a former U.S. military base near the central city of Tikrit, in June 2014, according to The Christian Post.

Masoum said the 36 ISIS fighters were sentenced to death in February by the central criminal court in Baghdad.

Survivors of that massacre, mostly military students, recalled that the ISIS militants promised their captives that they would be sent back to their families. The captives were divided into two groups based on their religious sects and put on lorries.

However, they were taken to a riverbank instead and killed with machine gun fire. Almost all those massacred were Shia Muslims, according to reports.

The ISIS later released videos showing hundreds of men being executed with machine guns.

On Friday, a new video released by ISIS shows the group's child soldiers executing five Kurdish fighters, according to Fox News.

The 9-minute video was posted online by ISIS leaders and was first reported by Middle East Media Research Institute, which tracks terrorist groups' communication throughout the region.

The children, who appear to be as young as 10 years old, shout "Allah Akbar," lower their guns and shoot the kneeling men in the backs of their heads. Friday's video was believed to be the first showing a mass execution carried out by multiple children, who are known as the "cubs of the Caliphate."