On June 20, the United States 10th Army Air Missile Defense Command engaged in an air defense exercise over the Black Sea alongside Romanian forces in Capu Midia, Romania. Known as Saber Guardian, the exercise integrated Patriot, Stinger, and Hawk missile systems from the United States to test allied interoperability and improve readiness to shoot drones flying over the area. According to Col. David Shank, commander of the 10th Army Air Missile Defense Command, Soviet SA-6 and SA-8 missiles were also integrated but presented difficulties during the live-firing exercise. This is the first time Patriot surface-to-air missiles were fired over continental Europe. Other exercises reportedly took place in Bulgaria and Hungary.