Police arrested on Friday a former official of Japan's Air Self-Defense Force on suspicion of leaking information seven years ago on U.S.-made military aircraft designated as a top secret by a Japanese law.

So Kanno, a 58-year-old former colonel who left the ASDF in 2017, allegedly showed data on the capability of early warning aircraft displayed on a personal computer to a trading company employee who was not authorized to access the information at the Iruma Air Base in Saitama Prefecture around Jan. 9, 2013, the police said.

Kanno is also suspected to have given the employee a USB memory device containing the data, which are designated as a special defense secret under the 1954 law based on the Japan-U.S. Mutual Defense Assistance Agreement. He has denied the allegation, according to investigators.

It is the third alleged violation of the law to be investigated by the police.

Following the arrest, Defense Minister Taro Kono told reporters no leakage of the information to a third country has been confirmed.

Kono expressed regret over the arrest, saying it "can damage public confidence and the trusting relationship between Japan and the United States."

Kanno was the planning division chief of the research and development department of the ASDF's Air Development and Test Command Headquarters at the time of the alleged leakage, according to the police.

The U.S. government provided Kanno with the confidential information around 2010, the police said. The trading firm employee passed the USB device on to an employee of a U.S. aircraft maker, which was a rival to the maker of the early warning aircraft in question around July 2013.

The rival maker later notified the U.S. government of the alleged information leak, according to the police.

The police have searched several locations, including Kanno's home.

The trading firm employee has admitted to the allegation, but will not be subject to criminal penalties owing to provisions of the law, the police said.

The law bans collecting or leaking of special defense secrets such as structures and capabilities of warships, aircraft and other equipment supplied from the United States to Japan based on the bilateral agreement. Violators could face a maximum of 10 years in prison.


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