An image pulled from an Islamic State video shows the child, above, who appeared to pull the trigger on two alleged spies for Russia. (Via Site Intelligence Group)

The Islamic State released a video on Tuesday that appeared to show a child killing two men accused of spying for Russia. In the video, the two men, who said they were from Kazakhstan and Russia, said they had been working with the Federal Security Service (FSB), the Russian intelligence agency, to infiltrate the extremist organization.

In an interview at the start of the video, produced by al-Hayat Media Center, a man who gives his name as Mamayev Jambulat Yesenjanovich says he was working to “gather information about fighters from Russia” and to obtain computer data. The Russian man, Ashimov Sergey, says he was sent to kill an unnamed man and locate the residence of the Islamic State's leader.

At the end of the video, the two men are shot with a pistol by a child at an undisclosed location.

An image from the video of one of the purported spies, who gave his name as Ashimov Sergey. (Via Site Intelligence Group)

The other purported spy, a man named Mamayev Jambulat Yesenjanovich. (Via Site Intelligence Group)

The Russian government has not confirmed that any agents were killed, and the FSB told the Russian news agency Ria Novosti that it had "no information at all."

However, Mark Galeotti, an expert on Russian security services with New York University, said it was plausible that the men were working in some capacity for the FSB.

"These guys by their own admission were FSB assets rather than officers and the tradecraft described is plausible," Galeotti said in an e-mail. "The FSB can and does operate abroad in support of its domestic security mission and given the concern about connections between IS and the North Caucasus insurgents, then it is highly likely that the FSB is seeking to penetrate the former."

Although there was initially some skepticism about whether the killings were faked, Eliot Higgins, a British blogger who has closely tracked the war under the name Moses Brown, told The Washington Post that he had concluded that they were real. Higgins says the boy in the video was featured in a separate Islamic State video late last year, in which he said he was from Kazakhstan.