MOSCOW (Reuters) - Five Russian citizens may have been killed in Syria in clashes with U.S.-led coalition forces this month, but they were not Russian military personnel, a Russian foreign ministry spokeswoman said on Thursday.

“Based on preliminary information, as a result of an armed encounter, the reasons for which are now being investigated, we could be talking about the deaths of five people,” the spokeswoman, Maria Zakharova told a briefing.

“The assumption is that these are Russian citizens. But all that needs to be checked, in particular, of course, their citizenship, are they indeed citizens of Russia, or of other countries,” she said.

“These are not Russian service personnel,” Zakharova said, referring to the casualties in Feb. 7 clashes near the Syrian city of Deir al-Zor.

Associates of Russian private military contractors fighting alongside government forces in Syria have said there were large-scale casualties among the contractors when U.S.-led coalition forces clashed with pro-government forces in Deir al-Zor province on Feb. 7.

Zakharova said media reports about dozens or hundreds of Russian dead in the Syria clashes were “disinformation”. She added that U.S. actions in Syria were probably designed to undermine the country’s territorial integrity.