Four-men, two of United States nationality and two from Britain, were arrested last week of using the banned drug in violation of Japan’s strict drug laws.

Tokyo-based Aggreko Events Services Japan confirmed four employees were arrested and apologised for causing trouble for people and Olympic officials.

In a statement, the company said it was cooperating with the investigation and pledged to abide by the rules.

Tokyo 2020 said that they had been informed "that four individuals have been arrested for alleged violations of the Narcotics and Psychotropics Control Law".

NHK public television reported the four men entered Japan between February and May and were living in Tokyo.

They reportedly were drinking at a bar in Tokyo’s entertainment district of Roppongi, where one of them allegedly broke into an apartment complex, leading to police questioning and arrests.

The four men denied the police allegations, but they tested positive for cocaine, NHK said.

"Should the allegations turn out to be true, Tokyo 2020 will issue a strict warning to the company and advise them to take all possible measures to ensure that such an incident does not happen again," organisers said in a statement.

The International Olympic Committee said that the arrests were "an individual issue and a question for the local justice authorities".

The incident took place before a state of emergency took effect yesterday in Tokyo that mainly attempts to curb public alcohol consumption during the Olympics, due to open on July 23 and conclude on August 8.

It asks bars and other such venues to close early or not sell alcohol for six weeks.

The conduct of accredited foreign visitors to these Games is under the spotlight with the majority of Japanese citizens wanting the event either cancelled or postponed because of fears it will lead to the import and spread of COVID-19.

Aggreko Events Services confirmed in January a revised contract for Tokyo 2020 reportedly worth $315 million (£227 million/€265million).

The Glasgow-based company became a Tokyo 2020 sponsor in December 2018 and was given the category of temporary electricity generation.

It is providing temporary electricity system to support the Games, including supporting operations at the International Broadcast Centre, the Main Press Centre and the Athletes’ Village.

It is also supporting functions such as broadcast, technology and sport lighting in 43 venues.

Aggreko have a history of supporting the Olympics having supplied the power at Beijing 2008 and London 2012, as well as Pyeongchang 2018.