Speaking at a news briefing on Saturday night, an official from the high-tech Haidian District in western Beijing said that the authorities had temporarily cordoned off the infected person’s residential compound and workplace. Health officials collected 2,430 samples for testing from people linked to the two locations.

The detection of the highly-transmissible Omicron coronavirus variant in Beijing comes as China has been racing to stamp out a series of concurrent outbreaks around the country as part of a broader effort to adhere to the government’s policy of “zero tolerance” for the coronavirus.

Authorities in Beijing in particular have been on heightened alert. The city is China’s political center and home to the country’s top leaders. It is also now gearing up for the arrival of thousands of Olympic athletes, officials and journalists who will stay in a tightly-restricted bubble in the city without having to do the mandatory quarantine that is required of most inbound travelers to China. The Olympics are set to start on Feb. 4.