Beijing reported 54 new locally transmitted COVID-19 cases between from Thursday to Friday afternoon, bringing the total number of infections to 1,336 since April 22. Fifteen districts are affected, Liu Xiaofeng, deputy director of the Beijing Center for Disease Prevention and Control, said at a news conference on Friday.

"Of the new infections, 52 were reported in controlled zones, and two were found during mass testing at the community level," he said. "Of the 54 new cases, 51 were related to the recent clusters."

Beijing recently reported several clusters involving a university, a wholesale market, a subway renovation project, a bus station and a branch of a logistics company, totaling more than 100 cases.

Of the 1,336 cases identified as of Friday afternoon, Chaoyang district had 409, followed by Fangshan, which reported 367 since April 22. Fengtai reported 203 cases and Haidian reported 147 during the same period.

As of Friday, Beijing had 15 high-risk areas for COVID-19 and 23 medium-risk areas.