Authorities in Norway launched a probe into the death of 23 people who passed away shortly after receiving the Pfizer-BioNTech vaccine against Covid-19. Several others have also fallen sick soon after getting vaccinated.

Pfizer and BioNTech are working with the Norwegian regulator to investigate the deaths and said that the number is not alarming "and in line with expectations".

Norway has given at least one dose to about 33,000 people, focusing on those considered to be most at risk if they contract the virus, including the elderly. The Pfizer-BioNTech Covid-19 vaccine approved late last year has been used most broadly, with a similar shot from Moderna Inc. approved earlier this month also now being administered.