“Today (Monday 21st) we received formal confirmation which shows that a number of our first-team squad have tested positive for Covid-19.

“We have informed the EFL and Tottenham Hotspur and will make a further announcement regarding Tuesday’s match shortly.”

EFL clubs no longer have to conduct mandatory tests on their players and staff for Covid-19 on a weekly basis this season, as is still the case in the Premier League.

But, ahead of the midweek tie, Spurs paid for Orient to test their squad and staff, the PA news agency understands.

The Orient statement continued: “We have also informed Mansfield Town, Plymouth Argyle and Oldham Athletic, our three most recent opponents, prior to the public release of this information.

“Leyton Orient’s priority is the health and well-being of its players and staff. Those who have tested positive will now strictly follow government self-isolation guidelines.

“The Breyer Group Stadium and training ground facilities will be closed until further notice.”

Plymouth said they had arranged a “precautionary round of Covid-19 testing” ahead of their match with Shrewsbury on Saturday and Mansfield have confirmed they will do similar ahead of this weekend’s fixture with Exeter. Both clubs added no-one had shown any coronavirus symptons.

PA understands there is no protocol in the EFL competition regulations for this eventuality, in terms of whether the match should be forfeited or rescheduled.

The EFL said it was awaiting results of discussions between club medics and Public Health England before deciding whether the game could go ahead.

It said in a statement: “The EFL has been made aware of positive test results recorded at Leyton Orient and is currently awaiting the outcome of discussions between the club and Public Health England which will determine what, if any, action is required outside of adhering to current protocols and guidance.”

O’s boss Ross Embleton was due to speak at a press conference on Zoom at 3pm to preview the game with Spurs, but that has now been cancelled.

The cup tie with Tottenham was an emotional fixture for the two clubs given the connection of the late Justin Edinburgh, who died last June at the age of 49 following a cardiac arrest.

Edinburgh won the FA Cup and League Cup at Spurs before he turned his hand to management and guided the O’s to the Vanarama National League title in April 2019.

Given Tottenham’s packed fixture schedule, with a Europa League tie on Thursday in Macedonia and potentially another next week if they triumph at Shkendija, the Premier League side have little wriggle room to rearrange the Carabao Cup third-round tie.

The fourth round of the tournament is due to take place the week commencing September 28, with the winner of the Breyer Group Stadium clash drawn to host Chelsea or Barnsley.