The athletes were caught drinking in a park in the athletes’ village on Friday night, Toshiro Muto told a news conference, in contravention of Covid-19 measures at the Games.

“We are looking into the matter. We will take appropriate steps based on our findings,” he said.

Police were also at the scene, he said, adding it was not clear what action they took, if any.

Muto did not give details of the number of athletes involved or their nationalities.

Organisers previously said athletes are permitted to drink alcohol only in their rooms and only if they are alone, as a precaution against Covid-19.

The Games are taking place in Tokyo without spectators and athletes and Olympic visitors have remained in a “bubble” with regular testing for the coronavirus.