The southern Chinese metropolis of Shenzhen traced and tested 2,913 people after a new asymptomatic case of COVID-19 was found on Wednesday. All of the nucleic acid test results were negative, said local authorities.
A total of 27 surrounding samples were also collected, all of which tested negative.
The new asymptomatic case was a close contact of an imported COVID-19 case confirmed on Tuesday, the municipal health commission said.
The imported case was a Hong Kong truck driver who transports goods between Shenzhen, south China's Guangdong Province, and Hong Kong. Authorities have placed 52 people under isolated observation, including the driver's 11 close contacts.