Japanese investigators say an arrested former employee of Tokyo-based telecommunications giant SoftBank Corporation admitted he received personal benefits from a Russian official.
Forty-eight-year-old Yutaka Araki allegedly accessed the company's confidential information on a corporate server in February last year. He was arrested on Saturday on suspicion of violating a law aimed at preventing unfair competition.
Araki told police that he passed the information on to an official in his 50s at Russia's Trade Representation in Japan.
Investigators say Araki repeatedly met with the official at places like restaurants in the Tokyo area and cited Araki as saying he received money for his personal use.
Police say a former official at the Trade Representation is also suspected of involvement. That person has already returned to Russia.
Police are asking Russia through diplomatic channels to make the two available for questioning.
Police say the confidential information was about equipment such as telecommunications base stations.
Police say telecommunications are regarded as important infrastructure and that information related to them is a major target of spying activity.