The National Health Commission said six people were confirmed infected in Qingdao City, Shandong Province, on Monday. The last time an infection was reported which was not related to coming from overseas was August 15.
Local city officials announced plans to conduct PCR tests on all 9 million residents or so within five days. They said more than 3 million tests were completed by Tuesday morning.
Officials added that all six cases were traced to a single hospital, so there was little risk of the virus spreading in the community.Chinese authorities conducted large-scale testing in July when the virus spread in Dalian, Liaoning Province, and in Urumqi, in the Xinjiang Uygur Autonomous Region. They say they have since kept the spread of the virus in check.