No new cases of COVID-19 were reported inside the Beijing Olympics "closed loop" on Thursday for the first time, a win for organizers who have gone to extreme measures to prevent the Games from seeding an outbreak that leaks into the public.

The Beijing Games have taken place inside a bubble, without paying spectators and with all participants — athletes, team officials, media, volunteers and staff — tested daily.

Some overseas analysts warned that the Winter Games would put further pressure on China's "COVID zero" stance, especially as authorities battled the new and more infectious omicron.