CHANGSHA -- The city of Zhuzhou in Central China's Hunan province has closed cinemas, entertainment venues and tourist sites after it reported new asymptomatic coronavirus infections.

Zhuzhou has since Thursday reported six asymptomatic cases, who had shared a boat on a river cruise in the city of Changde, also in Hunan, with three confirmed cases and another asymptomatic case, said the city's headquarters on COVID-19 prevention and control.

The city has suspended all on-site meetings and mass gatherings, and all residents are urged not to leave the city unless necessary, according to the headquarters.

Also on Friday, the city of Zhangjiajie in Hunan closed all its tourist sites and upgraded 11 neighborhoods to medium-risk areas for COVID-19. The city known for its scenic mountains on Thursday reported one confirmed case of COVID-19.