A Japanese man who was imprisoned on espionage charges in China says he met another Japanese national convicted of similar offenses at the prison where he was housed. The Japanese national died while serving his sentence.

NHK interviewed Suzuki Hideji. He belongs to an organization that promotes ties between Japan and China.

Suzuki returned to Japan earlier this month after completing his sentence in China. He was detained in Beijing in 2016 on suspicion of endangering the nation's security. A Chinese court later ruled that he was involved in spying activities. He was sentenced to six years in prison. The hearings were held behind closed doors.

Suzuki maintained his innocence. He said he was never a spy and that he had no reason to engage in spying activities. He was critical of the arrest and the judicial ruling by the Chinese authorities.

Suzuki said he met another Japanese man at the prison in Beijing. He said the man had been detained in 2015 on espionage charges and was sentenced to 12 years in prison.

The man became ill while he was serving his sentence. Suzuki said the individual died in February of this year. The man was in his 70s.

The man reportedly told Suzuki that he had visited China often because he liked the country.

The individual is said to have told Suzuki that he wanted to boost economic ties between China and the northern Japanese prefecture of Hokkaido, where the man used to live. Suzuki said he felt sorry for the individual.