Six people have tested positive for coronavirus in an outbreak at a test and trace call centre in North Lanarkshire.
Sitel, which carries out contact tracing for NHS England, said it was aware of a “local outbreak” at its Motherwell site.
Deputy First Minister John Swinney told BBC Radio’s Good Morning Scotland the call centre has been closed.
He said “extensive contact tracing” was under way.
Sitel said it was “urgently investigating” the outbreak with Public Health Scotland.
The company said it had requested that all staff who have been working at the site undergo testing within the next 24 hours.
A spokeswoman for NHS Test and Trace said everyone at the site is currently working from home while a deep clean takes place.
NHS Test and Trace is a service operated by the NHS in England to track and help prevent the spread of Covid-19 south of the border.
Mr Swinney told the BBC that the situation came to light at 08:00 on Sunday and since then a number of contacts of the people who tested positive have been identified.
It was a “pretty realistic conclusion” that there had been transmission of the virus in the office, he added – but an investigation into how it spread is being carried out.
Mr Swinney also said work would need to be undertaken to “get an understanding” of how guidance was being followed within the facility.
When asked if penalties could levied against Sitel, Mr Swinney said: “These are all issues that will be explored, but what our primary focus is on is to make sure that we interrupt any transmission of the virus.
“The virus is at a very low level within Scottish society today, the compliance efforts of members of the public have successfully reduced the prevalence of coronavirus, but we have to keep it that way.”
Mr Swinney added that actions being taken by NHS Lanarkshire and North Lanarkshire Council were “reassuring”.
Concerns had been raised after 23 new cases of Covid-19 in Scotland were announced on Sunday, although only three of these were in the Lanarkshire health board area.
This followed 21 cases being confirmed on Saturday, with both of these figures the highest recorded since mid-June.
However the number of new positive test results dropped back to seven on Monday, with First Minister Nicola Sturgeon welcoming “a reduction compared to recent days”.
She said all cases “will still be closely examined and contract tracing undertaken as appropriate”.
Dr David Crome, a consultant in public health medicine at NHS Lanarkshire, said the health board was investigating the situation and putting measures in place to reduce risk.
The Scottish government said contact tracing is under way following the detection of “a small number of potentially linked cases in North Lanarkshire”.
“Where potential clusters of cases develop we must find them and act quickly to prevent further spread and we are grateful to local partners for their swift response,” a spokesman said.
The spokesman said “a small increase in the number of cases is not unexpected as lockdown is lifted”, adding that it highlights the importance of the public co-operating with contact tracers as well as following guidelines on social distancing and wearing face coverings.