The Pentagon ordered a company-sized element of U.S. Marines to conduct an aerial assault drill near a small U.S. base in southeastern Syria called the At Tanf garrison amid new concerns of Russian operations nearby. Reports said that the Russian military has utilized a deconfliction hotline a number of times over the past week to warn the U.S. military of upcoming Russian and Syrian military operations aimed at destroying the last pocket of rebels from the Idlib region.