Beijing to test 20 million

China's capital Beijing has widened its Covid-19 mass testing from one district this week to most of the city of nearly 22 million, adding to expectations of an imminent lockdown similar to Shanghai's.

It began testing the residents of its most populous district of Chaoyang on Monday. But by the end of the day, even though only a fraction of the results were out, the city decided to conduct tests on 10 other districts and one economic development zone by Saturday.

Beijing's decision to now test roughly 20 million comes just days after tens of infections were found.