The holds of the freighter Thielbek were normally used for bulk cargo such as coal, grain or ore. Shortly before the end of the war, the ship was used to hold around 2,500 prisoners from the Neuengamme concentration camp together with several hundred guards and crew.
On 3 May 1945, the heavily overloaded Thielbek was attacked in Neustadt Bay together with the passenger liner Cap Arcona by British fighter-bombers.
The aircraft attacked with cannon fire, bombs and rockets.
The Thielbek sank within about fifteen minutes, taking nearly 3,000 people with it according to the figures cited here.
Victims drowned, burned or died from the effects of explosions and gunfire.
Survivors in the water were also exposed to fire from attacking aircraft.
The nearby Deutschland was also hit and capsized during the attack.