According to the report, the IS issued a video challenging Putin earlier this week. In the video, IS fighters posed on the top of Russian military equipment, including a fighter jet captured in Syria. As per a transcription of Agence France-Presse, the fighters warned Putin that they would send the Russian jets sent to Syria back to Moscow and would liberate Chechnya and the entire Caucasus.
They also told Putin through the video that the latter's throne was under threat and would fall in the face of their aggression, the Washington Post report quoted the AFP transcription as saying.
The IS has an estimated 200 Chechen fighters in its ranks, the report said.
Russia is an old ally of Syrian President Bashar-al-Assad and provides him military hardware. Moscow had opposed the West in taking strong steps against the Assad regime and sought reconciliation with the Assad regime but it did not succeed.