Russia’s Foreign Ministry, in its first confirmation that Russian citizens were involved in a military incident in Syria, says that five Russians who were not soldiers may have been killed in a clash with US-led forces in Syria last week. But it insisted that reports placing the Russian death toll in the dozens or hundreds were “disinformation.”

“According to preliminary information, we could be talking about the deaths of five people — presumably Russian citizens — as a result of an armed confrontation whose causes are being examined,” Foreign Ministry spokeswoman Maria Zakharova said on Thursday, alluding to an incident that occurred in oil-rich Deir al-Zor province on February 7.

“Reports about the deaths of dozens or hundreds of citizens are classic disinformation,” she added. “There were not 400, not 200, not 1,000, and not 10.”

Various US press reports have said that as many as 100 to 200 Russian mercenaries fighting for Syrian leader Bashar al-Assad died in the assault on the base held by US and Kurdish forces.