The Premier League has confirmed it has received six positive tests for coronavirus from three clubs after the first phase of mass testing.
A total of 748 tests have been carried out over the weekend and it is unclear whether they include players, non-playing staff or a combination of both.
Anyone who tests positive must now self-isolate for seven days and cannot attend the club training ground.
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Clubs and individuals have not been disclosed by the Premier League for data protection reasons, and clubs are expected to take part in a second phase of testing later this week.
However, on Tuesday night Burnley identified one of the six individuals as their assistant manager Ian Woan and said he is currently asymptomatic and self-isolating at home.
The data released on Tuesday reflects 19 Premier League clubs, with the last club undergoing testing on Tuesday, and all figures will be included in the results of the second round of testing due to be published on Saturday.
"The Premier League can today confirm that on Sunday, May 17 and Monday, May 18, 748 players and club staff were tested for COVID-19," a Premier League statement read on Tuesday.
"Of these, six have tested positive from three clubs. Players or club staff who have tested positive will now self-isolate for a period of seven days.
"The Premier League is providing this aggregated information for the purposes of competition integrity and transparency. No specific details as to clubs or individuals will be provided by the League and results will be made public in this way after each round of testing."
Premier League clubs can now resume training in small groups while maintaining social distancing, following the release of the test results.
Officials are optimistic about the Premier League restarting in June - some three months after football was suspended due to the coronavirus pandemic - but there is an acknowledgment that plans may not be sufficiently advanced to ensure a return to action on June 12, as initially hoped.
The Premier League has also been warned current coronavirus restrictions are likely to be in place long-term, with Public Health England advising them the public health situation is unlikely to change in the next 6-12 months.
At Monday's 'Project Restart' meeting, the 20 clubs did not discuss the possibility of curtailing the season - like in Scotland - and continued talks over the issue of neutral venues.
'We need to wait for trends'
Analysis by Bryan Swanson, chief reporter, Sky Sports News
The fact there are six positive tests must be taken seriously.
Those individuals, whether players or non-playing staff, will have to self-isolate for seven days before they take a further COVID-19 test.
They cannot attend the training ground and three clubs will now want to establish what contact those individuals had with other people, in particular in the same household.
In theory, they should have not have come into close contact with anyone outside their household since March, under the government's social distancing rules.
It is also important to highlight that more than 99 per cent of people have tested negative in the first round.
These figures, across 19 clubs, show that coronavirus is not widespread in Premier League clubs at the moment, at least not amongst the 40 people tested per club.
One club only carried out testing on Tuesday, and their data will be included in the next round of figures.
Up to 50 people from each club will be tested in each round going forward, twice a week, after a request by clubs, meaning up to 2,000 test results a week will be provided to the Premier League.
Prenetics, the company conducting the tests, has told Sky Sports News it can cope with increased demand.
The second round of test results are due to be published on Saturday before clubs hold talks next week about the potential return of contact training.
We need to wait for trends, using further rounds of results, before we can assess the significance of these figures and establish whether the authorities feel it is safe to resume competitive games next month.
Gary Neville has warned that more players may reject a return to Premier League training - but Jamie Carragher says he is increasingly confident that the league will resume this summer.
"I know there are Premier League clubs with five or six players who don't want to return or are uncomfortable with certain things around stage two or three," Neville told The Football Show.
"We do have more problems and issues to resolve over the coming weeks."
The league voted unanimously on Monday to start 'small group' training with immediate effect.
But Carragher doesn't believe the reluctance of a small number of players to return to training is likely to derail plans to resume the Premier League season this summer.
He said: "We have always said on this show that if a player does not feel safe or sound to go back, he can't go back. This was always going to be the case that maybe one or two players in every squad may not feel safe and may not want to go back.
"I do not think that would stop the Premier League going on. If players en masse said they did not want to be involved, then that would be a big problem.
"But if one or two players in every club, that is something the clubs and Premier League will just have to accept and try and get them on board going forward."
Watford captain Troy Deeney has said he will not return to training this week amid concerns for his own son's health, as well as that of BAME players.
"We're due back in this week. I've said I'm not going in. It's nothing to do with financial gain," Deeney said on Eddie Hearn and Tony Bellew's Talk The Talk podcast. "When I go into full detail about my personal situation, everyone here will go 'no problem'.
"My son is five months and he's had breathing difficulties. I don't want to come home and put him in more danger. You've got to drive in in your own kit, you can't have showers, then drive back in the same dirty kit you've got.
"If I'm putting my clothing in with my son's or my missus' it's more likely to be in the house."