This month's discoveries came after weeks of searching by crew members based on the research vessel Petrel. The vessel is owned by Vulcan Inc, a company created by the late Microsoft co-founder Paul Allen.

One ship, the Kaga, was discovered last week, while wreckage from another carrier, Akagi, was found on Sunday, Vulcan Inc. said in a press release.

"Every shipwreck we find reminds us all of the ultimate sacrifice made by those who served their countries," said Robert Kraft, Vulcan Inc.'s director of undersea operations, in a press release. "Our team is truly honored to have discovered the Japanese Flagship Carrier, Akagi."

A report on social media stated that the 55-year-old diver was ascending from a 91.5m (300ft) solo rebreather dive in Bonaire, and was found unresponsive on the reef at 24m (80ft) with the loop out of her mouth. (It is not known whether she had planned to dive to that depth or not). She was brought to the surface and medivaced. She did not regain consciousness. It is thought that all of her equipment was recovered. Her Inspiration rebreather head has already been downloaded for analysis. At the time of writing this piece, it is not known what happened.