Beijing reported two new locally transmitted COVID-19 cases between midnight and 3 pm on Sunday, and senior officials said the city's major epidemic control and prevention risks are from outside of the capital due to ongoing outbreaks in other provinces and increasing tourism during the summer vacation.

The two new cases, who live together in Beijing's Shijingshan district, arrived in Beijing on Wednesday and they both tested negative on the same day, according to Liu Xiaofeng, deputy director of the Beijing Center for Disease Prevention and Control, at a news conference on Sunday afternoon.

They developed symptoms including a headache and sore throat on Thursday and were confirmed to have been infected with COVID-19 on Sunday, Liu said.

He added residents who have been to Hainan province since July 23 should report to their residential communities, hotels or workplaces for epidemic prevention measures accordingly.

Sanya, a city at the southern tip of Hainan island, reported a total of 615 confirmed locally transmitted cases and 212 asymptomatic carriers from Monday to Saturday, according to the local COVID-19 epidemic prevention and control headquarters. A city-wide lockdown was imposed starting at 6 am on Saturday.