BEIJING (AP) – China has begun its most extensive lockdown in two years to conduct mass testing and control a growing outbreak in Shanghai. China’s largest city with 26 million people had handled past outbreaks with limited lockdowns of housing compounds or workplaces. But the citywide lockdown that started Monday will be China’s biggest since the 76-day lockdown of Wuhan in early 2020. Residents must stay home and deliveries will be left at checkpoints. All unessential businesses will be closed and public transport suspended. The lockdown will be done in two phases of five days each while the population is tested for the virus. Most of Shanghai’s cases are in people not showing symptoms, though they can still pass the virus to others.