Syria: USAF Airstrikes kill at least 100 Russian 'Wagner'-Mercenaries

Syria, February 2018. "This is a big scandal and a reason for an acute international crisis," said Vladimir Frolov, a former Russian diplomat and lawmaker who's now an independent political analyst. "But Russia will pretend nothing happened."

https://www.bloomberg.com/news/articles/2018-02-13/u-s-strikes-said-to-kill-scores-of-russian-fighters-in-syria

SAT-Image from one of the US-Airstrikes against RU-Mercs attacking SDF in Syria: