An ambitious underwater project commissioned by the British Broadcasting Company has unraveled 64-year-old secrets surrounding a massive naval battle during World War II, London's Daily Mail reported.

Operation Hailstone began on Feb. 17, 1944, when American forces bombed Truk Lagoon in the southwestern portion of the Pacific Ocean.

Over the next two days, the U.S. Navy sank 70 Japanese ships, destroyed 270 aircraft and killed an estimated 3,000 enemy servicemen.

The attack was so devastating that some historians refer to it as "the Japanese Pearl Harbor," although the Imperial Navy had already moved its battleships and aircraft carriers to safer locations.

The BBC commissioned a team of 30 divers, deep sea biologists and underwater cameramen to embark on the exploration.

"We were pushing the boundaries, spending extra-long periods as a visitor in an alien element," the Daily Mail quoted presenter-explorer Kate Humble as saying. "I'm not a brave person and I was nervous because every dive has its risks."

• Click here for the full report in the Daily Mail.