Japan's Health Ministry on Friday confirmed 41 new cases of coronavirus on a cruise ship currently quarantined off the coast of Yokohama. 

Authorities said in addition to 20 cases confirmed over Wednesday and Thursday, there are now a total of 61 cases out of 273 passengers tested on the Diamond Princess cruise ship. The vessel is carrying about three-thousand-700 crew members and passengers.

Twenty-one out of the 41 patients are Japanese, while the nationalities of others have yet to be revealed.

None of the nine South Koreans onboard are reported to have tested positive for the virus.

Most of them are in their 60s or older, while three are in between their 20s and 40s.

Authorities plan to continue monitoring all passengers and crew until the virus' 14-day incubation period ends.