TOKYO - Two athletes have tested positive for the coronavirus in the Tokyo Olympic Village after a team colleague was also infected, officials said on Sunday, raising fears of a cluster just days before the opening ceremony.

The first cases involving athletes in the Village come a day after a member of their entourage returned the first positive test in the complex, which will house thousands of athletes.

The three infections were revealed as competitors fly in from around the world for the pandemic-delayed Olympics, which are facing significant opposition in Japan due to their COVID risks.

Tokyo 2020 spokesman Masa Takaya said the three cases "were from the same country and sport". They are "isolated in their rooms and Tokyo 2020 is delivering meals to them", he said, adding that the rest of the team have also been tested. The team was not identified.

The Olympic Village, a complex of apartments and dining areas in Tokyo, will house 6,700 athletes and officials at its peak when the delayed 2020 Games finally get underway.

The Tokyo Games, which will be held largely behind closed doors to prevent infections, are unpopular in Japan where opinion polls have consistently demonstrated a lack of support.

Olympic officials have been at pains to play down the health risks of the Games, which are taking place in stringent anti-coronavirus conditions with athletes tested daily.

"Mingling and crossing of populations is very limited. We keep the risk to an absolute minimum level," Olympic Games executive director Christophe Dubi said on Sunday.

"We can ensure that transmission between the various groups is almost impossible."

Fifty-five cases linked to the Games, which open on Friday, have been discovered this month, including four athletes.

South Korean IOC member Ryu Seung-men tested positive on arrival in Japan and was placed in isolation, a spokesman for the Olympic body said.

On Saturday, International Olympic Committee president Thomas Bach appealed for Japanese fans to show support, saying he was "very well aware of the scepticism" surrounding the Games.