A massive World War II bomb that was dropped by the Royal Air Force in an attack on a Nazi warship in 1945 reportedly exploded on Tuesday during a delicate operation near the Baltic Sea. However, no one was harmed by the explosion.

The bomb, dubbed as "Tallboy", and also known as an "earthquake bomb", was discovered last year embedded at a depth of 12 metres (39 feet) with just its nose sticking out during dredging close to the port city of Swinoujscie in northwest Poland.

Grzegorz Lewandowski, spokesman for the Polish navy's 8th Coastal Defence Flotilla based in Swinoujscie was quoted by AFP as saying, "But in the end "the deflagration process turned into a detonation."

He also added, "There had been no risk to the individuals directly involved," he said, adding that the bomb."