The U.S. Department of State issued a new warning to Americans in Ukraine on Monday morning, telling them to “leave immediately” due to potential travel disruptions. “The Department of State continues to urge U.S. citizens to depart Ukraine immediately using commercial or private means due to the increased threat of Russian military action,” the State Department said in a press release. The agency said that the “security situation” in the Eastern European country remains “unpredictable” and may “deteriorate with little notice.” Meanwhile, Russian military operations might “severely restrict commercial air travel,” which would potentially impact U.S. citizens trying to flee, the State Department said. Early Monday, Ukraine and Russia again lobbed accusations at one another over alleged fighting in eastern Ukraine. After Moscow claimed that Ukrainian soldiers crossed into its territory and Russian forces killed five of its soldiers, Ukraine denied the allegations on social media. “No, Ukraine did NOT: …