Photo taken on Dec. 9, 2020 shows a sign board (R) reminding passengers in need to use a courtesy passage to pass temperature checkpoints set up to help control the spread of COVID-19 at Beijing Daxing International Airport in Beijing, capital of China. (Xinhua/Ju Huanzong)

BEIJING, Dec. 16 (Xinhua) -- China's civil aviation regulator announced on Tuesday the suspension for one week of three inbound flights after several passengers tested positive for COVID-19 on recent flights.

A total of five passengers tested positive on Ethiopian Airlines Addis Ababa-Chengdu flight ET636 on Dec. 3. Eight tested positive on Russia's Ikar Airlines Moscow-Zhengzhou flight EO429 on the same day, while six tested positive on Swiss International Air Lines Zurich-Shanghai flight LX188 on Dec. 7, said the Civil Aviation Administration of China (CAAC).

The suspension of the Ethiopian Airlines flight and the Ikar Airlines flight will commence from Dec. 21, while that of the Swiss International Air Lines flight will start from Dec. 27.

The CAAC introduced a reward and suspension mechanism on June 4 to further contain the spread of COVID-19.

According to the CAAC policy, if all inbound passengers on an airline test negative for COVID-19 for three weeks in a row, the operating airline will be allowed to increase its number of flights to two per week.

If the number of passengers testing positive reaches five, the airline's flights will be suspended for a week. The suspension will last for four weeks if the number of passengers who test positive for COVID-19 reaches 10.