The United States once tried to build a "tsunami bomb" designed to wipe out coastal cities by triggering huge underwater explosions.
The tests were carried out shortly before the end of the second world war off the coast of New Zealand, near to Auckland.
Code-named "Project Seal", the tests reportedly demonstrated that it was possible to create waves 33 feet high with a series of ten explosions.
According to the Telegraph, the operation was intended to create a possible alternative to the nuclear bomb.
In all about 3,700 bombs were set off during the tests, the paper said.
New Zealand author Ray Waru discovered the plans after searching through the country's national archives.
He told the Telegraph that the project was launched in June 1944 after a US naval officer E A Gibson noticed that blasts on coral reefs sometimes created large waves.
While America and New Zealand conducted several tests, the plans were eventually shelved in 1945.
Even so, experiments by the New Zealand government apparently continued until the 1950s - even as experts said that more than 2 million kilograms of explosives would be needed for a successful bomb.
"If you put it in a James Bond movie it would be viewed as fantasy but it was a real thing," Waru told the paper.
And if it sounds far-fetched, remember the US also planned to blow up the Moon. So in comparison, the ocean is nothing major.
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