TOKYO — Three more people on a cruise ship off Japan have tested positive for the new coronavirus, bringing the number aboard to 64, the government said on Saturday, with passengers facing a two-week quarantine.

The latest confirmation came a day after an additional 41 passengers were found to have contracted the virus, which has killed hundreds of people, most of them in China, where it has infected more than 30,000 on the mainland.

Japanese authorities have so far tested about 280 people on board the Diamond Princess, which was quarantined after a former passenger who disembarked in Hong Kong last month was diagnosed with the virus.

Test results from six more people were released on Saturday, with three of them confirmed infected, the health ministry said.

The three passengers are two Americans — a woman in her 60s and a man in his 70s — and a Chinese woman in her 30s, the ministry said without giving their names.

They have already been sent to hospital, it added.

There were more than 3,700 passengers and crew on the ship when it arrived off Japan's coast on Monday evening. It docked in Yokohama on Thursday to resupply for a quarantine that could last until Feb. 19.

One of those found infected is in serious condition. Many on board are elderly and at greater risk of developing complications from the virus.

Testing was initially carried out on those who displayed symptoms or had come into close contact with the former passenger diagnosed.

Passengers on the ship have been asked to stay inside their cabins to prevent new infections and expressed confusion and frustration.

Some passengers are reportedly complaining about the lack of medicine needed for their own chronic diseases. Public broadcaster NHK said about a half of the passengers are over 70.

Television footage showed a Japanese flag hung on a balcony with a message saying: "Drug shortage is serious."

The World Health Organization (WHO) called on Tokyo to provide sufficient support, including mental care, for the passengers and patients.

"There's a lot to do to support those patients. Not just from the point of view of their physical health but from a mental health perspective," Michael Ryan, head of the WHO's Health Emergencies Program, told reporters in Geneva on Friday.

"It's quite scary, very, very scary to be in that situation," he said. "It's a very stressful situation for those individuals."

But he also called for calm, saying: "Let's be careful here not to overreact. This is a very close community living in very close quarters."

Late Saturday, Japan's health ministry reported a fresh infection with the virus, bringing the number of cases identified in the country to 26 — aside from the infections on board the ship.

The patient, identified as a Japanese man in his 20s, was among passengers who returned to Tokyo from Wuhan on Friday on Japan's fourth flight bringing Japanese nationals home from the Chinese city, where the pathogen emerged.

Separately, the foreign ministry said a Japanese man in his 60s with a suspected coronavirus infection has died at a hospital in Wuhan.

He would be the first Japanese victim of the outbreak if his diagnosis is confirmed.

Prime Minister Shinzo Abe sent his condolences to his bereaved family and renewed his pledge to contain the outbreak.

"Protecting our people's lives and health is the top priority," Abe told reporters.

"I will do my best to prevent the spread and take necessary measures without hesitation." — AFP