The U.S. Navy took the unusual step Monday of releasing video of a Russian Su-24 aircraft flying past the right side of the guided missile destroyer USS Ross in the Black Sea. The video was distributed to make clear that the airplanes and ship had a routine encounter, contrary to Russian reports. It shows a warplane approaching from the distance and then quickly zooming past the American vessel. The Ross was 25 miles off the coast of Crimea in international waters when six Russian Su-24s went by. The Russian aircraft were not armed, according to a U.S. defense official, and the entire matter was considered routine. Russian media claimed that the planes forced the warship to head away from Russian territorial waters. But the U.S. Navy said the Ross never changed course and proceeded on its mission, which was in international waters. In a video released by U.S. Naval Forces Europe, one of the Russian planes is shown flying an estimated 500 meters (1,640 feet) off the side of the ship at an altitude of 600 feet. The Navy said it would not have released the video if it didn’t want to publicly counter the Russian reports. The incident comes as Defense Secretary Ash Carter warned about the danger of a summer offensive by pro-Russian separatists, who have seized Crimea from Ukraine. “We are looking at Russian activities, at the activities of separatists. It’s a serious possibility and a serious danger,” Carter told the BBC in an interview published Monday.