(Xinhua/Cheng Min)

Six more sight-seers were found to be infected with the novel coronavirus pneumonia (NCP) on the Diamond Princess cruise ship on Sunday, bringing the total to 70, according to Japanese news agency ANN. 

Japan's Ministry of Health, Labor and Welfare is testing more than 3,600 sight-seers and crew members who remain on board. 

As soon as the infection is confirmed, patients are removed from the ship and transported to a medical institution, said the ANN.

On Sunday morning, several medical personnel boarded the ship and people with severe symptoms were taken to hospital. Medical personnel from the Ministry of Health, Labor and Welfare dispatched a "­disaster medical assistance team" (DMAT) also boarded and provided medicines for approximately 500 people, the report said. 

The Diamond Princess was quarantined after a tourist, who disembarked in the Hong Kong Special Administrative Region last month, was diagnosed with the virus.

There were more than 3,700 sight-seers 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 February 19.

Many on board are elderly and at greater risk of developing complications from the virus. 

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