Russia's Defence Ministry said on Sunday that one of its top generals has been killed in an attack by Islamic State in Syria.
Russia has officially denied targeting the US -backed Syrian Democratic Forces with airstrikes in Deir ez-Zor as Russian-backed Syrian government forces move right up against the SDF.
"A representative of U.S. command in Al Udeid, Qatar, was notified in severe form that attempts to attack from districts where SDF fighters are located will be repelled", he said.
The SDF, an alliance of Kurdish and Arab fighters, captured the Conoco plant in eastern Syria's Deir Ezzor province on Saturday.
Separately, Russia denied carrying out an air strike that a US-backed Syrian force said killed one of its fighters and injured several others.More news: Abdullahi 'Proud' Of Home Eagles Despite WAFU Cup Final Defeat, Hails Ezenwa
More news: Korea: Temblor Detected in North Korea Not a Nuclear Blast
More news: Tropical Storm Pilar pelts Mexico coast near Puerto Vallarta
On Tuesday Russia's Defence Ministry said the waters of the Euphrates had risen as soon as the Syrian army began crossing it, suggesting this could only have happened if upstream dams held by the US -backed opposition had been opened.
A communiqué of the Ministry affirms that the members of the so-called Democratic Army of Syria (EDS), considered by the West as moderate opposition and supported by the Pentagon, moves freely between the positions of the ISIS, and the Euphrates river.
As the largest of those groups, the Kurds can expect tensions with the Syrian military and its Russian backers to grow, as all parties converge on the last remnants of the Islamic State. The United States has made similar accusations against Moscow, asserting that Russian forces say they are targeting IS fighters, but are in fact targeting US -backed forces.
The motive was "to stop the successful advance of the Syrian army", Russia's commander in Syria said.
-Gen. Igor Konashenkov said in a statement.
"International problems are suffering from the fact that Russian Federation and the US can't coordinate their actions because of unrelated issues", he said, suggesting that Obama's opposition over Russia's support for Assad, and its incursions into Ukraine, had prevented effective cooperation. Russian officials did not immediately respond to a request for comment on the latest allegation.