A Japanese doctor treating new coronavirus patients in New York, a hotspot of infections, on Saturday issued a strong warning over the virus situation in Tokyo, saying that the Japanese capital now "looks like" New York two to three weeks ago.

The daily number of people confirmed to have the virus in Tokyo exceeded 100 for the first time on Saturday. In New York state, this happened about three weeks ago, on March 12.

"News from Japan show people gathering," Yuichi Shimada, doctor at the cardiovascular medicine department at the Columbia University Irving Medical Center, said.

"People in Japan do not seem serious enough about the situation," the 37-year-old doctor said, adding, "In New York three weeks ago, people weren't taking basic infection prevention measures, such as wearing face masks, washing hands and avoiding closed, crowded places involving close contact."

The cumulative number of people found infected stood at 113,704 in New York state as of Saturday, with the death toll reaching 3,565.

In New York, ambulances are seen ferrying coronavirus patients to hospitals all the time, Shimada said. "Ambulances are mobilized with the same frequency as that in the aftermath of" the Sept. 11, 2001, terrorist attacks on the United States, he said.

The emergency departments at New York hospitals are flooded with coronavirus patients, he also said.

The first coronavirus case in the US state was reported on March 1. The infected person was a woman who returned from Iran, and the infection route for the woman was identified.

For the person who was found infected next, however, the source of infection was unknown.

"In Tokyo as well, infection routes have not been identified for many infected people," Shimada said, warning that the virus may already be spreading widely in the Japanese capital.

"New York is one of the only few US cities where people can commute by public transportation systems, and it has many restaurants and bars where people can gather," Shimada said.

He added: "The virus can spread easily in such major cities, and this has actually happened. The situation in Tokyo is very similar to that of New York."

"I think the virus could spread explosively (in Tokyo) if people remain optimistic about the situation," Shimada said, adding, "I really hope Tokyo will not make the same mistake as New York."

JIJI Press