On January 28, 1964, The U.S. State Department angrily accused the Soviet Union of shooting down an American jet. The plane was on a training mission over West Germany and strayed into East German airspace during a storm. Three U.S. officers aboard the plane were killed in the incident. The Soviets felt it was an obvious intrusion. The U.S. said it was a mistake. The incident was an ugly reminder of Cold War-era tensions.