Japanese officials have confirmed 99 more people infected by the new virus aboard the quarantined cruise ship Diamond Princess, bringing the total to 454.

The ministry has been carrying out tests on passengers and crew on the ship, docked in Yokohama, a port city near Tokyo.

The 14-day quarantine for those on the ship was due to end Wednesday.

Outside China, the ship has had the largest number of cases of the COVID-19 illness caused by the virus that emerged in China late last year.

Meanwhile, two charter flights carrying passengers from that cruise ship have landed in the United States.

The first plane carrying American passengers landed at a Northern California air force base just before midnight Sunday.

A second flight touched down at a San Antonio air force base around 2 1/2 hours later, early Monday.

Passengers will be quarantined for two weeks to make sure they don't have the new virus that's been spreading in Asia.

Japan's defense minister tweeted earlier that Japanese troops helped transport 340 U.S. passengers from the port to Tokyo's airport.

About 380 Americans were on the cruise ship. (AP) 

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