MOSCOW (Reuters) - A man identified as a Russian mercenary leader in Ukraine and Syria by an authoritative website attended a Kremlin reception earlier this month, Vladimir Putin’s spokesman said on Thursday, raising questions about the man’s links to the authorities.

Mercenaries who fought in Ukraine have told Reuters that the man, who went by the nomme de guerre “Vagner,” led a unit of Russian mercenaries in Ukraine and Syria.

Fontanka, an authoritative Russian-language website, has published what it says is the only known photo of “Vagner.” The website said his name was Dmitry Utkin. Reuters could not verify the image or the name.

Dmitry Peskov, Putin’s spokesman, told reporters in a conference call on Thursday that Utkin had attended a Kremlin reception on Dec. 9 for Russians who had received state decorations.

Peskov said he knew nothing about mercenaries and did not know under what other names Utkin might be known.

“Dmitry Utkin really was there,” said Peskov.

Utkin had been invited as a holder of the Cavalier of the Order of Courage, an honor that recognizes selfless acts of courage and valor, said Peskov.

Russian authorities have denied using mercenaries, and under Russian law it is illegal to work as a private military contractor in another country.