China plans to ease Covid rules for athletes inside the bubble at the Winter Olympics.

Athletes traveling to Beijing for the Winter Olympics will be able to skip quarantine if they are fully vaccinated, a signal that China is willing to ease some restrictions to ensure that teams make it to the Games in February.

But athletes will still face strict rules, and punishment for violating them, including expulsion, the Beijing Olympics’ organizing committee said on Wednesday. The committee members did not specify what offenses would merit expulsion. But the Beijing Olympics are already shaping up to be the most extraordinarily regulated, large-scale sporting event since the start of the pandemic.

Organizers have outlined a “closed-loop management system” that will restrict athletes, officials, journalists and staff members to a bubblelike environment for the duration of their stay in China. Those in the bubble must be fully vaccinated or spend 21 days in quarantine, and they will also be tested for the virus daily. Currently, all overseas arrivals to China must undergo quarantine.

Other potential penalties for violating the rules include warnings, temporary suspension of credentials or other “relatively serious consequences,” Zhang Jiandong, a senior official on the committee, said at a news conference.

Tickets for the Winter Olympics will be sold exclusively to domestic spectators. Beijing’s Covid protocols so far appear more strict than those of the Tokyo Olympics in July and August.

At the Tokyo Games, athletes were not required to be vaccinated, and they were allowed limited contact with people outside the bubble. Some athletes violated the rules, including not wearing masks. And other people went on unauthorized sightseeing excursions. No participants, however, were actually removed from competition unless they tested positive for the virus, and the organizers allowed almost no spectators.

China enforces a strict “zero Covid” policy, carrying out widespread lockdowns and testing to eliminate even small-scale outbreaks. On Tuesday, it locked down Lanzhou — a northwestern city of about four million people — as officials tried to quash a small Covid outbreak.