Russia says it killed U.S.-trained opposition fighters in Syria

Russia's defence ministry said on Friday that its air force had "destroyed" a group of U.S.-trained opposition fighters in Syria on Aug. 4.

Reuters was not able to immediately verify the claim.

Russian forces have helped Moscow's ally, Syrian President Bashar al-Assad, to turn the tide against anti-government rebels, some of them backed by the United States or Turkey, in a civil war that has lasted over a decade.