Officials in Norway say at least 50 people in Oslo have been infected with the Omicron variant.
The cases are connected to a company's recent Christmas party in a restaurant in the capital, officials said on Thursday.
The Oslo Municipality said in a statement that more cases are expected.
Officials are trying to trace transmission routes from the party.
Much remains unknown about the new variant including whether it is more contagious, whether it makes people more seriously ill and whether it can thwart vaccines.
The Norwegian Institute of Public Health said that those affected live in Oslo and surrounding municipalities.
Australian Associated Press
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