China has taken a zero-tolerance approach to COVID cases, quickly tracing and testing wide swathes of its population to prevent the spread of the virus.
Local infections accounted for 40 of the new cases, compared with only five a day earlier, the National Health Commission said in a statement on Monday.
Thirty-nine of the local cases were reported in the eastern province of Jiangsu, and one in the northeastern province of Liaoning, it said.
Nanjing, the capital city of Jiangsu province, was conducting a second round of nucleic acid testing of its 9.3 million residents on Sunday, the official China Daily said on Monday.
The city raised its COVID risk level in one area to high, while changing other areas to a medium risk level, the paper added. The move comes after it suspended its subway line and took other measures to control the new cluster.
Total confirmed COVID-19 cases in mainland China stand at 92,605, and the death toll remains at 4,636.