Intelligence gathered by U.S. forces, believed to be related to the movements of foreign militaries, was included in state secrets leaked by a Maritime Self-Defense Force captain recently dismissed for the breach, government sources said Tuesday.

The revelation that the captain gave classified information to a retired MSDF admiral has drawn criticism from the United States over lax information management by the Self-Defense Forces, causing concern within the Japanese government about the two countries' cooperation in the future, the sources said.

In March 2020, Takashi Inoue, 54, disclosed secret information regarding "situations surrounding Japan" as well as the MSDF's troop operations and training, according to the Defense Ministry.

The ministry said the former admiral requested an MSDF unit in charge of collecting and analyzing information in January 2020 to brief him about the latest state of security affairs but had not demanded that classified information be disclosed.

Although there is no evidence of the information being passed on to others through the former admiral, there are fears that the incident could impact the future provision of information from the United States, whose intelligence plays an integral role in the operation of SDF units, the sources said.

At a press conference Monday, Adm. Ryo Sakai, chief of staff of the MSDF, promised to "strive to restore the trust of the countries concerned."

Defense Minister Yasukazu Hamada echoed the sentiments at a press conference Tuesday, saying the leak "undermines public trust and is extremely regrettable. We take the matter very seriously and will do our utmost to restore trust."

Regarding preventative measures to be compiled by the end of March, Hamada stressed the need to "take drastic measures, so they are known throughout the Defense Ministry," adding that stricter rules regarding interaction between active and non-active personnel were "a given."

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