Japanese Navy last year lost a $5 million worth unmanned submersible in the Tsugaru Strait.
The remote-controlled submersible was used in a survey of the underwater terrain between Honshu and Hokkaido, AFP reports.
The Navy lost the submersible after the cable connecting it to the ship was damaged.
The search for the submersible, which was organized right after the incident, lasted for nine days and yielded no results.
According to AFP, the Ministry plans to conduct further investigation.
Subsea World News Staff, January 29, 2014; Image: Wikimedia