The two who tested positive are among 1,500 competitors and staff who have come into the country since the test events began in early October.

Huang Chun, the deputy director general of the Pandemic Prevention Office for the Games, said they had come on a chartered plane for luge training and the Luge World Cup season opener in Yanqing.

Neither showed symptoms and both were allowed to train but had to stay in a quarantine hotel and eat meals alone.

The athletes have not been named.

China has among the strictest coronavirus prevention policies in the world.

Entry to the country is restricted, and almost everyone who does must quarantine in a hotel for at least two weeks, even if they are vaccinated and test negative.

The quarantine requirement is being waived for the test events and the Games, but participants must live and compete in isolation from the rest of the population in China, known as a "closed-loop" system.

"Closed-loop management not only serves the Games well, but also prevents further spread of the virus," Huang said.

"This is our goal."

Organisers also expressed their sympathy for Polish luger Mateusz Sochowicz who fractured his leg at the National Sliding Centre this week in a crash that has been blamed on human error.

Sochowicz, who was 20th in last season’s World Cup rankings, crashed into a gate that should have been open at the venue which is set to host the bobsleigh, luge and skeleton events at Beijing 2022.

"We express our sincere sympathy to the injured athlete," said Zhao Weidong, the director general of the media department for the Games.

"No one wants to see athletes injured."