Facebook is closing its three London offices and telling staff to work from home after an employee was diagnosed with COVID-19.
The employee who was diagnosed with the virus was normally based in Singapore, the company told Sky News, but had visited the London offices between 24-26 February.
Facebook has just over 3,000 employees in London.
Sky News was unable to learn how many individuals had been in direct contact with the person who was diagnosed with COVID-19, but Facebook said that the company had been in contact with them all.
These individuals are being asked to self-isolate and be vigilant in monitoring whether they develop symptoms.
The company is now also reaching out to any employees and contingent workers based in other offices that visited London over the past few days to warn them.
In a statement, a spokesperson for Facebook said: "An employee based in our Singapore office who has been diagnosed with COVID-19 visited our London offices 24-26 February 2020.
"We are therefore closing our London offices until Monday for deep cleaning and employees are working from home until then."
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