13 years of civil war
The Syrian Army, along with what is believed to be Iranian-backed militias, took control villages east of the Euphrates river near the city of Deir ez-Zor that were under the control by Kurdish-led forces in a rare clash with the Syrian Democratic Forces. The territory was later recaptured by U.S.-backed forces in a counter-attack spearheaded by the YPG with help from U.S.-led coalition jets that took off from American bases in northern Syria. The U.S. military says in a statement that the "coalition used established deconfliction channels to de-escalate the situation".
Sources: Reuters