Much of Shanghai in lockdown as mass testing starts

China began its most extensive lockdown in two years Monday to conduct mass testing and control a growing outbreak in Shanghai as questions are raised about the economic toll of the nation's “zero-COVID” strategy.

The citywide lockdown that will conducted in two phases will be China’s most extensive since the central city of Wuhan. Shanghai's Pudong financial district and nearby areas will be locked down from Monday to Friday as mass testing gets underway.

In the second phase of the lockdown, the vast downtown area west of the Huangpu River that divides the city will start its own five-day lockdown Friday. Shanghai detected another 3,500 cases of infection on Sunday.

China has reported more than 56,000 confirmed cases nationwide this month.