Seventy-three more patients died of the novel coronavirus outbreak in China on Thursday, taking the toll to 636, the country’s National Health Commission said. The country had reported 73 deaths on Wednesday as well, the highest single-day fatalities so far.

Only four of these deaths were reported outside the Hubei province, the epicentre of the outbreak. The number of confirmed cases of infection rose to 31,161, while 1,540 patients were discharged from hospitals after being cured on Thursday. The commission’s data is from mainland China – there were 34 cases in the special administrative regions of Macau and Hong Kong, with one death. A person has died in the Philippines too.

The World Health Organization named 15 laboratories that are providing “reference testing support” for the coronavirus. National Institute of Virology, Pune, is one of them.

One of the persons who died on Thursday was Li Wenliang, a 34-year-old Chinese doctor who was among the first to warn the world about the possible novel coronavirus outbreak in December. Li, a doctor at Wuhan Central Hospital, had written on a Chinese social media site, that seven patients had been diagnosed with an illness similar to Severe Acute Respiratory Syndrome, or SARS, and quarantined in his hospital.

Li had urged his colleagues to wear protective clothing at work to avoid getting infected. However, the local public security bureau had accused him of “making false comments” that “severely disturbed the social order”. The authorities later apologised to Li after criticism from the country’s Supreme Court.

Chinese President Xi Jinping on Friday spoke with United States President Donald Trump on phone about the outbreak, and said that China had “spared no effort in fighting the epidemic”, state broadcaster CCTV reported. Xi told Trump that China was “fully confident and capable of defeating the epidemic”.

Meanwhile, 61 people have tested positive so far on a cruise ship off the Japanese coast, which has been quarantined for over two weeks, BBC reported. Around 3,700 people are on board.

On Thursday, India said it could consider evacuating Pakistanis stranded in China if the situation arises, ANI reported. External Affairs Ministry spokesperson Raveesh Kumar said the Pakistani government had not made any such request so far. “But, if such a situation arises and we have resources then we will consider it,” he said.

India had evacuated more than 640 of its citizens, and seven Maldivians, last week from China. A viral video on social media showed a Pakistani student expressing disappointment at his government that it had not yet planned to evacuate them.

In India, there are three positive cases – all from Kerala. They recently returned from the Chinese city of Wuhan. On Tuesday, India tightened visa restrictions for travellers from China amid the novel coronavirus virus outbreak. India has evacuated 654 individuals — 647 Indians and seven Maldivians — on two Air India flights from Wuhan till now.