Treasure hunters claim to have found the wreck of a British steamer that was torpedoed by the Germans off the US coast in 1942 while carrying a cargo of Soviet precious metals worth £2 billion ($2.95 billion).
Greg Brooks, the co-founder of a US treasure hunting company called Sub Sea Research, said he was certain the sunken ship was the SS Port Nicholson and that its cargo of platinum, gold and industrial diamonds packed in wooden boxes was intact.
"We have verified these boxes have unusually high mass as one would expect for bullion," he said. "I am going to get it one way or another even if I have to lift the ship out of the water."
If confirmed, the discovery would be one of the biggest treasure troves to be found on the sea bed, and would likely lead to a messy international legal battle for ownership rights.
Mr Brooks found the wreck in 2008 but kept his find secret until now while quietly securing salvage rights. He said his team had identified 30 boxes scattered around the wreck which he believed were stuffed with platinum ingots.
The SS Port Nicholson was sunk by two torpedoes from a U-boat with the loss of six lives as it made its way from Halifax in Canada to New York.
Escorted by an unusually high number of warships, it was reported to be carrying a Soviet cargo of precious metals meant to recompense the US government for military supplies.
The cargo was reportedly accompanied by two Soviet envoys who survived the attack only to then mysteriously disappear when brought ashore in the United States. The Soviet government is reported to have subsequently reimbursed the US government for the lost payment.
Mr Brooks said he had found the wreck in 700 feet of water off Cape Cod off America's east coast using shipboard sonar and had later used underwater cameras and remotely operated underwater vehicles to explore the wreck.
Underwater vehicles have been unable to even lift the boxes because of their weight and Mr Brooks is raising fresh funds to finance the salvage operation.
Some experts have advised caution, saying it is too early to say whether Mr Brooks's suspicions about the ship's cargo are right. The British Government is watching proceedings and has not ruled out making an ownership claim.
Anthony Shusta, a Florida-based lawyer representing the Government, said it was unclear whether the ship had such a treasure trove. "We are still researching what was on the vessel," he said. "Our initial research indicated it was mostly machinery and military stores."
The Daily Telegraph, London