Shanghai will continue to implement closed-off management until further notice, local health authorities announced Monday. 

Authorities said the decision was made while they continue to review test results, arrange re-tests and other related work.

The metropolis ordered citywide antigen testing on April 3 and nucleic acid testing on Monday amid efforts to contain the recent resurgence of COVID-19.

The megacity in east China initiated temporary closed-off management from late March in two phases. 

The first batch covered the area on the east side of the Huangpu river which separates the city. And the second was for people on the west side of the river.

Read more:

Shanghai to conduct new round of mass virus screening

Shanghai found 425 confirmed locally transmitted COVID-19 cases and 8,581 asymptomatic carriers as of Sunday. 

More than 38,000 medics from 15 Chinese provinces were dispatched to Shanghai for support, the National Health Commission of China said on Monday.