Tianjin City in north China detected the Omicron variant of COVID-19 in a person who came from overseas, local health authorities revealed on Monday, the first known Omicron infection found in the Chinese mainland. 

Details on the person's nationality or travel history were not immediately disclosed.

Officials said the individual is an asymptomatic COVID-19 patient and its respiratory specimen has showed existence of the Omicron variant on December 9 after tests ran by Tianjin health authorities and Chinese Center for Disease Control and Prevention confirmed the result. 

This person was under closed-loop management since entry to Tianjin and is now being treated in isolation in hospital.