The Thielbek was a 2,815 GRT freighter that was sunk along with the SS Cap Arcona and the SS Deutschland during British air raids on May 3, 1945 while anchored in the Bay of Lübeck with the loss of 2,750 lives. The ship was a passenger ship flying a white flag and had been commandeered along with the Cap Arcona to take on board prisoners from the Neuengamme, Stutthof, and Mittelbau-Dora concentration camps.