During World War II, six German saboteurs who secretly entered the United States on a mission to attack its civil infrastructure are executed by the United States for spying. Two other saboteurs who disclosed the plot to the FBI and aided U.S. authorities in their manhunt for their collaborators were imprisoned.

In 1942, under Nazi leader Adolf Hitler’s orders, the defense branch of the German Military Intelligence Corps initiated a program to infiltrate the United States and destroy industrial plants, bridges, railroads, waterworks, and Jewish-owned department stores. The Nazis hoped that sabotage teams would be able to slip into America at the rate of one or two every six weeks. The first two teams, made up of eight Germans who had all lived in the United States before the war, departed the German submarine base at Lorient, France, in late May.

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Just before midnight on June 12, in a heavy fog, a German submarine reached the American coast off Amagansett, Long Island, and deployed a team who rowed ashore in an inflatable boat. Just as the Germans finished burying their explosives in the sand, John C. Cullen, a young U.S. Coast Guardsman, came upon them during his regular patrol of the beach. The leader of the team, George Dasch, bribed the suspicious Cullen, and he accepted the money, promising to keep quiet. However, as soon as he passed safely back into the fog, he sprinted the two miles back to the Coast Guard station and informed his superiors of his discovery. After retrieving the German supplies from the beach, the Coast Guard called the FBI, which launched a massive manhunt for the saboteurs, who had fled to New York City.

Although unaware that the FBI was looking for them, Dasch and another saboteur, Ernest Burger, decided to turn themselves in and betray their colleagues, perhaps because they feared capture was inevitable after the botched landing. On July 15, Dasch called the FBI in New York, but they failed to take his claims seriously, so he decided to travel to FBI headquarters in Washington, D.C. On July 18, the same day that a second four-man team successfully landed at Ponte Vedra Beach, Florida, Dasch turned himself in. He agreed to help the FBI capture the rest of the saboteurs.

Burger and the rest of the Long Island team were picked up by July 22, and by July 27 the whole of the Florida team was arrested. To preserve wartime secrecy, President Franklin D. Roosevelt ordered a special military tribunal consisting of seven generals to try the saboteurs. At the end of July, Dasch was sentenced to 30 years in prison, Burger was sentenced to hard labor for life, and the other six Germans were sentenced to die. The six condemned saboteurs were executed by electric chair in Washington, D.C., on August 8. In 1944, two other German spies were caught after a landing in Maine. No other instances of German sabotage within wartime America has come to light.

In 1948, Dasch and Burger were freed by order of President Harry S. Truman, and they both returned to Germany.