Frame grab from footage released by Russia‘s Defence Ministry shows airstrikes carried out by Russian air force in Syria.

Three serving or former Russian soldiers have been geolocated by photographs in Syria, including locations near Hama, Aleppo and Homs, Russian bloggers said on Sunday, suggesting the Kremlin’s operation stretches well beyond its air campaign.

Russia first launched air strikes to support President Bashar al-Assad in Syria’s four-year civil war on Sept. 30 but has repeatedly said it has no intention of mounting a ground operation.

It has instead said it will limit its help to military trainers, advisers and deliveries of military equipment.

U.S. security officials and independent experts told Reuters last week that Moscow had increased its forces in Syria to 4,000 personnel from an estimated 2,000. A U.S. defense official said multiple rocket-launcher crews and long-range artillery batteries were deployed outside four bases the Russians were using.

Sunday’s report by Conflict Intelligence Team (CIT), a group of Russian investigative bloggers, said that photos on social media had been used to geolocate three Russian serving or former soldiers in Syria.

“Although we still don’t have indisputable evidence of Russian servicemen taking a direct part in the fighting on the ground in Syria, we believe the situation observed contradicts the claims of Russian officials that Russian troops are not taking part and are not planning to take part in ground operations,” CIT said.

Russia’s military jets are based in Latakia in western Syria, far from where the three men were geolocated.

Social media screenshots

The Russian defense ministry did not respond to a written request for comment on Sunday to respond to CIT’s findings and to clarify the nature of its ground operations.

CIT published screenshots from a social media account belonging to Ayas Saryg-Ool, a soldier it said served in Russia’s 74th Separate Motorized Rifle Brigade, and from an account belonging to Vladimir Boldyrev, who it suggested was a Russian marine from the 810th Separate Marine Brigade.

It showed both of them had recently posted pictures with geolocation tags in Hama Province. Saryg-Ool’s page, which had previously shown him posing with a heavy machine gun and in the cab of what CIT said was an artillery tow truck, was not available on Sunday.

When contacted by Reuters on Sunday, Boldyrev denied in a message he was an acting serviceman sent to Syria, saying the picture of him and other soldiers had been taken when he was a conscript. He did not explain why one of his own pictures was geotagged Hama, Syria.

CIT also published screenshots from the Instagram page of Ilya Gorelykh, who it said had served in Russia’s GRU special forces in the past.

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