TOKYO (Reuters) - Japan has “grave concerns” about the jailing of three Hong Kong activists and has conveyed its worries to China over the situation, chief government spokesman Katsunobu Kato said on Thursday. Hong Kong authorities on Wednesday sentenced prominent democracy activists Joshua Wong to more than 13 months in prison over an unlawful anti-government rally in 2019, the toughest sentence for an opposition figure this year. They also jailed Wong’s colleagues Agnes Chow and Ivan Lam for 10 and seven months, respectively. Chow speaks fluent Japanese and is well-known in Japan. “Japan increasingly has grave concerns about the recent Hong Kong situation such as sentences against three including Agnes Chow,” Kato told a regular news conference. “We have conveyed our concerns to China about Hong Kong at various opportunities,” he said. Reporting by Tetsushi Kajimoto; Writing by Chris Gallagher; Editing by Christopher Cushing Our Standards: The Thomson Reuters Trust Principles.