Arsenal manager Mikel Arteta has tested positive for coronavirus.
The Gunners have closed their training ground and club staff who had recent contact with Arteta will now self-isolate.
The Premier League will hold “an emergency club meeting” on Friday to discuss future fixtures.
“This is really disappointing but I took the test after feeling poorly,” said Spaniard Arteta, 37. “I will be at work as soon as I’m allowed.”
Arsenal expects a “significant number of people” will self-isolate, including the “full first-team squad”.
“The health of our people and the wider public is our priority and that is where our focus is,” said club managing director Vinai Venkatesham.
“We are in active dialogue with all the relevant people to manage this situation appropriately, and we look forward to getting back to training and playing as soon as medical advice allows.”
Arsenal are due to play at Brighton in the Premier League on Saturday (15:00 GMT).
Arsenal’s Premier League match with Manchester City on Wednesday waspostponed as a “precautionary measure”and several Gunners players went into self-isolation after Olympiakos owner Evangelos Marinakis contracted coronavirus.
Arsenal said Marinakis, 52, met a number of their players when the Gunners hosted the Greek side in a Europa League match two weeks ago.
The club saidno players or staff would be testedfor coronavirus.
Manchester City defenderBenjamin Mendy is self-isolatingas a precaution after a member of his family was admitted to hospital displaying symptoms of coronavirus.
Three Leicester City first-team players have also self-isolated aftershowing symptomsof coronavirus.
How things unfolded on Thursday
- 14:06 GMT – Brendan Rodgers says three Leicester City players have self-isolated after showing symptoms.
- 16:00 GMT – Manchester City’s Champions League last-16 tie with Real Madrid, due to take place on Tuesday, is postponed.
- 17:25 GMT – Prime Minister Boris Johnson says the UK government is considering banning sporting fixtures – but it will not happen immediately.
- 20:45 GMT – Manchester City says defender Benjamin Mendy is self-isolating as a precaution.
- 21:30 GMT – The Premier League announces all this weekend’s games “will go ahead as scheduled”.
- 22:17 GMT – Arsenal says manager Mikel Arteta has tested positive for coronavirus.
- 22:33 GMT – The Premier League announces it will hold “an emergency club meeting” on Friday to discuss future fixtures.