In an effort to contain an outbreak of COVID-19 on Monday, authorities in the southern Chinese city of Shenzhen temporarily closed Huaqiangbei, the largest electronics market in the world, and suspended service at 24 subway stations.

The vast marketplace, which houses thousands of shops selling microchips, telephone parts, and other components to manufacturers, will remain closed until September 2 due to the closure of three significant buildings.

Local community officials confirmed Monday’s closure to Reuters, while three people working there said building managers had told them to work from home.

The same official Shenzhen channels called a halt to subway services at 24 stations in the central districts of Futian and Luohu.

On Monday, the tech hub of 18 million people reported nine symptomatic and two asymptomatic cases from testing the previous day.