Islamic State militants in Syria beheads alleged Russian spy - See pic

Since Moscow began air strikes, on various hideouts of ISIS, in support of Syria`s government, this is the first video from the dreaded group to show the apparent execution of a Russian.

Beirut: A new video has gone viral on social media Wednesday purporting to show a Russian-speaking Islamic State (IS) militant beheading an alleged Russian spy from the group’s ar-Raqqah Province, and also can be heard threatening Russia with more attacks.

Since Moscow began air strikes, on various hideouts of ISIS, in support of Syria's government on September 30, this is the first video from the dreaded group to show the apparent execution of a Russian.

In the clipping, a prisoner wearing the orange tunic and trousers often seen on captives of IS can be seen.

Speaking in Russian, the detainee allegedly confesses to being recruited by Russian intelligence to gather information on IS and its members from the Caucasus.

A Russian-speaking fighter then addresses Moscow directly, warning that its forces will be defeated and its troops killed.

The video, which bears the logo of the group's media office in the Syrian province of Raqa, ends with the beheading of the detainee.

IS has claimed the execution before of alleged Russian spies.

In January, it released a video purporting to show a young boy shooting dead two men accused of working for Russian intelligence services.

IS controls large swathes of Syria and Iraq, which it rules as a self-declared "caliphate."

The city of Raqa, in Syria's northern Raqa province, is a stronghold of the group and its de facto Syrian capital.