Just before 6 a.m., 1 million litres of water gushed out of the 25-meter-high aquarium, and glass and other debris were swept out of the structure, which also houses a hotel and cafes.
Two persons were reported to have had minor injuries in Berlin, and rescue dogs were being prepared to search the structure for anyone who might be buried by debris.
It was hypothesised that nighttime lows of minus 10 degrees Celsius produced a breach in the tank, which gave way under the weight of the water.
There was no proof that the occurrence was the result of an attack, according to the police, who claimed they were still looking into the incident’s cause.
Witness Gwendolin Szyszkowitz stated to the German television channel n-tv that she first thought there was a bomb when she heard a huge blast.
The aquarium’s owners claim it boasts the largest circular tank in the world, which before the tragedy held 1,500 tropical fish from 80 different kinds.
Berlin’s aquarium, which had its most recent renovation in 2020, is a popular tourist destination.
One of the attractions highlights was the 10-minute elevator trip through the tank.