Also Read | The curious case of the glowing beachesAll rural villages in Shunyi district on the outskirts of Beijing are locked down until a fresh round of mass testing has been completed, district official Zhi Xianwei said at a press briefing Monday.The move means around 518,000 residents will not be permitted to leave their villages until they have undergone testing.Officials also said locals would be under "closed management", suggesting they will be barred from leaving their residential compounds.The district, which has a total population of 1.2 million, is home to many rural migrant workers.Zhi said officials would "knock on doors...