In an apparent response to the Russian airstrikes in Syria, the Islamic State (ISIS) has released a chilling new video vowing attacks in Russia "very soon'' and specifically threatening to "make their [Russians'] wives concubines and their children slaves.''

The release of the video came nearly two weeks after ISIS affiliate Sinai Province claimed it blew up the St. Petersburg-bound Metrojet plane on Oct. 31 that killed 224 people, mostly Russians returning home. Moscow and Cairo both dismissed the initial claim.

The five-minute video footage was gruesome as images of beheadings, prisoners being decapitated and shot at point-blank range and scenes of Russian troops were being shown while an eerie chant of male voices was being heard on the background, according to MailOnline.

The ISIS warning says: "The lions of Ummah have awoken. They have raised their swords. O, filthy kufr (infidels), you are not brave at all. The sound of your voice has been silenced. We will take through battle the lands of yours we wish, so much of your lands. Soon very soon, the blood will spill like an ocean... we will make your wives concubines and make your children our slaves.''

The warning was reportedly delivered in the form of an Islamic chant known as Nasheed. Lyrics of this have also been posted on the group's propaganda page.

Another chant posted by the extremists read: "We came to you with slaughter, defying death. In your gun barrel we have seen paradise. Europe is shaking, Russia is dying. The Kremlin will be ours.''

Kremlin spokesman Dmitry Peskov told Breitbart that Russian security agencies will look into the video.

"I do not know the authenticity of this video, I do not know the authenticity of these sources, but in any case no doubt this will be material for review by our special (security) services,'' said Peskov.

ISIS also said in an audio statement posted online that they will prove their claim about the bomb attack on the Russian jet in due time. "Prove that we didn't bring it down, and how it came down. We will detail how it came down at the time of our choosing.''

Western intelligence officials suspect the ultra-hard-line Sunni group of planting a bomb in the Russian passenger jet. They also named secretive leader Abu Osama al-Masri, 42, as the likely head behind the plot.

ISIS has previously called for attacks on Russia and the United States in revenge for airstrikes on its positions in Syria that started late September.

The new video bears all the hallmarks of the skillfully edited and highly choreographed videos released by the jihadi group's Al Hayatmedia Centre, most notably the sickening footage showing the Jordanian pilot being burned to death in February, the MailOnline said.