Norwegian authorities say the number of positive Covid-19 tests onboard Hurtigruten’s cruise ship MS Roald Amundsen has risen to 53.

The outbreak is related to two voyages around Svalbard, one from July 17-24, and one from July 24-31, with boarding and disembarking in Tromsø.

The Norwegian Institute of Public Health, said nine new cases had been registered in its latest update today, taking the total number of positive cases to 53, 37 of which are among the crew and 16 passengers.

The passengers on the two voyages must be quarantined for 10 days, and followed up by the local health services where they live, it said, noting that the quarantine period for the first voyage has now expired.

Hurtigruten’s chief executive has already apologised for ‘failures’ over the outbreak, and the line has denied an attempted cover-up.

Its expedition cruises have been suspended as a result of the outbreak.