Japan, the United States and South Korea must persuade Beijing to stop sending people who flee North Korea back to the country, a Japanese aid worker who recently served eight months in a Chinese prison for trying to smuggle two such people to safety, urged Thursday.

Recently returned to Japan, Takayuki Noguchi, 33, was detained in December in the city of Nanning, Guangxi Province, while trying to help two Japan-born North Koreans flee to Vietnam via China.

He was sentenced in late June to eight months in prison and fined 20,000 yuan (about 260,000 yen). He was released Aug. 9, after his time in custody was taken into account.