A new video released by ISIS militants purports to show the execution of two Russian spies at the hands of a child.

The nearly eight-minute video, called "Uncovering an Enemy Within," was released by Al Hayat, the English-language media arm of the Islamic State.

See also: How ISIS is training child recruits

The video includes interviews with two men who identify themselves as Russian Intelligence (FSB) agents Jambulat Yesenjanovich Mamayev from Kazakhstan and Serge Nikolayavich Ashimov, who says he used to be Muslim. The men state they were sent to spy on the militants in territory held by the Islamic State to relay information back to Russia in exchange for money. Later in the video, they appear to be executed by a young boy with a handgun.

"My mission was to come to Sham and get close to [an unnamed militant] and inform the FSB about him, and also to gather information about fighters from Russian and send the information to Russia," Yesenjanovich says in the video.

A man who says he is a Russian spy is seen on an Islamic State video released on Tuesday, Jan. 13, 2015. Image: Militant video

"I was required to send every information about the fighters in Sham and to determine the place of residence of an Islamic State leader," the second man, Nikolayavich, says, adding that he was sent to kill one of the group's leaders.

A man who says he is a Russian spy is seen on an Islamic State video released on Tuesday, Jan. 13, 2015. Image: Militant video

The video then cuts to show the two men kneeling in the dirt in front of a militant and a young boy holding a handgun. The adult fighter reads from the Quran and says, "Allah has gifted the Islamic State's security agency with the apprehension of these two spies... By Allah's grace, they are now in the custody of the lion cubs of the Caliphate."

Two men are seen kneeling before they are purportedly executed by a young boy at the encouragement of an Islamic State militant. Image: Militant video

The young boy then steps forward at the encouragement of the ISIS militant, raises the gun to the back of the first man's head and fires. He does the same with the second man, appearing to shoot him twice more after he slumps forward.

Charlie Winter, a researcher on jihadism in Syria and Iraq at London-based counter-extremism organisation Quilliam, says the boy, no older than 10, has appeared in previous videos released by the Islamic State.

Boy in latest #IS video appears in earlier release, "Race Towards Good", which featured recruits from #Kazakhstan. pic.twitter.com/M6dj01zhCG — Charlie Winter (@charliewinter) January 13, 2015

The group has reportedly been grooming children to join its militant group through "cub camps" targeting those younger than 16. Iraqi security officials have said that the children, deemed "Cubs" in ISIS propaganda videos, are being taught the principles of jihad at several camp across Iraq and Syria.

The children wield AK-47s, watch beheadings and train in military drills before graduating from the camps within one month, according to the unnamed official.

Photos described as showing "A Tour Inside Shaddad Al-Tounisi Camp for Cubs of the Islamic State" were circulated by accounts associated with the group in September. The photos show children participating in military drills, doing pushups and climbing ropes. While it is unclear where or when they were taken, an ISIS flag can be seen in several of the photos, and were circulated on social media accounts associated with the group.

Some have questioned the authenticity of the most recent video, which Mashable has viewed but will not show here due to its graphic nature.

The news agency Storyful has not been able to verify that the two men were, in fact, killed, noting the absence of any entry or exit wounds; however, it notes that one of the victims appears to bleed from the nose after being shot, suggesting it was not staged. It also shows bullet casings flying from the handgun. If authentic, it is likely the men were speaking under duress before they were killed.

"The FSB has no comment on the situation," an official from Russia's Federal Security Service, also known as the FSB, told state-run RIA Novosti news service. RIA Novosti also quoted an official at Russia's embassy in Damascus as saying they had no further information.

Additional reporting by Megan Specia and Christopher Miller.