SHANGHAI -- Over 14 million Shanghai residents in Puxi, or areas west of the Huangpu River, took nucleic acid tests on Friday, amid the city's second phase of closed-off management, a local official told a press conference on Saturday.

Shanghai reported 260 confirmed locally transmitted COIVD-19 cases and 6,051 asymptomatic carriers on Friday, said Wu Qianyu, an official with the Shanghai Municipal Health Commission, attributing the daily rise in positive cases to a wider range of screening.

Starting on March 28, the megacity in East China began to enforce temporary closed-off management in two phases to track infections and curb the spread of the virus.

Mass nucleic acid testing in areas east of the Huangpu River started on March 28 with the first phase of closed-off management in place. The second phase of closed-off management came into force in areas west of the river on Friday.