Qingdao in East China's Shandong province reported a new imported COVID-19 case and eight asymptomatic cases from abroad on Saturday, according to the official WeChat account of the city's health commission.

All the infections affect Chinese staff members of China Petrochemical Corporation working in Kuwait, took charted Air China flight CA042 and arrived at Qingdao Liuting Airport on Friday, the health commission said.

All passengers and flight crew on the same plane are under medical observation. A total of 350 people are believed to have had contact with the infected.

The confirmed case, a 32-year-old man surnamed Zhao, is a Shandong native. He was taken to a designated hospital for COVID-19 patients after showing symptoms, including a sore throat and cough. The result of his nucleic acid test for the novel coronavirus came out positive on Saturday. He is under treatment in a designated hospital.

The eight asymptomatic cases, all males aged from 22 to 45, also are from Shandong province. Their nucleic acid tests were confirmed positive on Saturday and they are isolated for further medical observation.