ISIS claims to behead Russian 'spy,' warns of terror attacks in Moscow, Washington and New York

A new ISIS video shows a Russian-speaking terrorist murdering a man he accused of being a Russian spy.(Screenshot of ISIS video from YouTube)

Two video clips have been released by the Islamic State (ISIS) showing the beheading of a Russian "spy'' and threatening to inflict terror in Moscow as well as in Washington and New York in the United States.

The eight-minute video is believed to have come from the terrorist group's stronghold in Raqqa, Syria where Russia—joined later by France and Britain—has been conducting airstrikes, Fox News reported.

According to the report, the first part of the video showed the captive, who identified himself as Khasiev Magomid, 23, from the Chechen city of Grozny, kneeling before an ISIS militant.

His killer then said in Russian that the airstrikes ordered by President Vladimir Putin against the ISIS "has only made us more certain and more firm.''

"Here today, on this blessed land, the battle [against Russia] begins," the militant said.

"We shall kill your children for every child you've killed here," he states. "And we will destroy your homes for each home you destroyed here."

The militant warned that the Russian people are likely to face another defeat—referencing to their retreat in Afghanistan in the 1980s—and that their people "would not be safe in their homeland," Fox News said.

In the video clip, Magomid claimed he was recruited by Russia's intelligence services and assumed the alias of Haroon when he travelled to Syria in 2014.

He added that he was tasked with collecting information on ISIS fighters of Russian origin and especially those who wanted to return to the Caucasus region and Russia to carry out attacks.

In the other video, two camouflage-garbed men are seen sitting cross-legged on a beach with rifles propped against their shoulders and talking about the Paris attacks that left 130 dead.

"Praise be to Allah who allow martyrdom-seeking lions to storm the capital of France," said one man in reference to the Nov. 13 Paris bombing.

"France was the beginning," he warned. "Tomorrow it will be Washington, it will be New York and it will be Moscow."

A Middle East Media Research Institute analysts believe that the first man speaks Arabic, while the second speaks in English with an African accent, said the report.

The warning from the ISIS and its affiliates about the "coming attacks" in the two U.S. cities is reportedly the fifth since the deadly Paris bombings.

Whether it's true or not, Steve Stalinsky, executive director of MEMRI, said any threat from ISIS could not be ignored.

"Any threat from ISIS when they mention a specific city should be taken seriously," he said. "They have been successful over the last months, and all of a sudden they are regularly mentioning New York and Washington, and that had not always been the case."

The Russians are among the citizens of several nations who are known to have joined ISIS in Syria and Iraq.

Earlier reports said apart from helping Syrian President Bashar Assad maintain his stay in power, Russia's deadly airstrike campaign in Syria aims to target its citizens who have left home to join and fight with the terror group.