Pro-Kremlin Chechen leader Ramzan Kadyrov has claimed spies from his region of Russia are being sent to infiltrate the Islamic State group (ISIS or IS) and assist Moscow in its bombing campaign in Syria.
Kadyrov, who has led the North Caucasus region of Chechnya since 2007, made the claims in a preview of a documentary set to air on state television on Wednesday.
The documentary claims that "agents from special forces from Chechnya were embedded" in ISIS training camps to collect intelligence and help identify targets for Russian air strikes.
Quoting Kadyrov, it said that the "best fighters" from mostly Muslim Chechnya have managed to create an "intricate agent network directly inside IS," although some have been killed.
"We unfortunately have had some losses," Kadyrov said in an interview in the documentary.
"But they knew where they were going, what they were getting involved in. They went there so we can live peacefully in Chechnya and all over Russia."
The preview showed Kadyrov at a training camp in Chechnya where heavily-armed men were shooting at targets and completing obstacle courses.
Chechen agents in ISIS "gather information about the structure and numbers of the terrorists and set targets for bombings," the documentary claimed.
There was no way to immediately verify Kadyrov's claims. Russian President Vladimir Putin has ruled out a ground operation in Syria.
Kremlin spokesman Dmitry Peskov declined to comment on what Kadyrov said.
A source in the Chechen leadership told Interfax news agency on Tuesday that "there have been people from Chechnya in the conflict zone on the territory of Syria and Iraq since the emergence of IS."
"These consist of self-organised groups of young men who aim to fight the terrorist organisation," the source said, adding that "none of them are members of the Russian armed forces or working for the interior ministry."
ISIS fighters in December released a video showing the beheading of an ethnic Chechen man who had made a filmed confession that he worked for Russian special services to spy on ISIS in Syria.
Kadyrov at the time conceded that Russian secret services were operating in Syria to "carry out missions to neutralize bandits", but said the execution victim was not working with them.
At the same time, some Muslim Chechens and other Russians have gone to Syria to support ISIS jihadists.
According to figures released by Russia's FSB security service in December, nearly 2,900 Russians are fighting or have fought with the extremists in Iraq and Syria.
AFP contributed this report.