(Bloomberg) -- A county neighboring Beijing has been locked down after finding one preliminary positive Covid case, the second time this week an area close to the capital has used the measure in a reflection of mounting efforts to curb transmission.

Xianghe, in the northern province of Hebei, issued a stay at home order to its 384,000 residents from Friday and suspended all non-essential business and public transport. People can only go out for urgent medical services or to take part in mass testing.  

The county is about 30 miles southeast of Beijing and residents often commute to the city for work. It follows a snap lockdown in Zhuozhou, which borders the capital to the southwest, on Tuesday after finding eight Covid cases. 

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The swift moves indicate how determined authorities are to keep the virus from spreading to Beijing, which has managed to keep its daily case tally below two digits for more than two months. China’s political center has deployed strict rules to keep the virus at bay, requiring residents to get a PCR test every three days in order to take transport and enter most venues, and ban entry to travelers coming from places that have had Covid.

Even with Beijing averting a widespread flareup, the lockdowns of commuter areas risk disruptions to the capital as many workers will now be stuck at home. Xianghe and Zhuozhou haven’t said when their restrictions will lift.

Read more: Chinese State Media Defend Covid Zero, Warn Against ‘Lying Flat’

A substantial virus incursion into Beijing would be a major test for China’s Covid Zero strategy, and risks occurring in the run up to a political meeting later this year when President Xi Jinping is expected to secure a precedent-breaking third term as leader.

China reported 1,501 local cases for Thursday, down from a peak of more than 3,400 last week, as outbreaks in tourism destinations such as Hainan and Xinjiang ebb.    

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