New York’s governor announced Tuesday he is sending the National Guard into a New York City suburb to help fight what is believed to be the nation’s biggest cluster of coronavirus cases — one of the most dramatic actions yet to control the outbreak in the U.S.

The move came as health authorities contended with alarming bunches of infections on both sides of the country and scattered cases in between.

Schools, houses of worship and large gathering places will be closed for two weeks in a “containment area” centered in New Rochelle, and the troops will scrub surfaces and deliver food to the zone, which extends a mile in all directions from a point near a synagogue connected to some of the cases, Gov. Andrew Cuomo said.

“It is a dramatic action, but it is the largest cluster of cases in the country,” he said. “The numbers are going up unabated, and we do need a special public health strategy.”

New Rochelle and surrounding Westchester County account for at least 108 cases out of 173 statewide. New York City, with 100 times the population of New Rochelle, has 36 known infections.

In Oakland, California, meanwhile, thousands of increasingly bored and restless passengers aboard a cruise ship struck by the coronavirus waited their turn to get off the vessel and go to U.S. military bases or back to their home countries for two weeks of quarantine. In Washington state, where at least 19 deaths have been connected to a Seattle-area nursing home, Gov. Jay Inslee announced new rules for screening health care workers and limiting visitors.

“If we assume there are 1,000 or more people who have the virus today … the number of people who are infected will double in five to eight days,” he warned.

On Wall Street, stocks climbed higher during the day, recouping some of their staggering losses from the day before. The United Nations closed its headquarters in New York to the public and suspended all guided tours.

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The virus has infected over 700 people in the U.S. and killed at least 27, with one state after another recording its first infections in quick succession. New Jersey reported ts first coronavirus death Tuesday. Worldwide, nearly 120,000 have been infected and over 4,200 have died.

For most people, the virus causes only mild or moderate symptoms such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia. Most people recover in a matter of weeks, as has happened with three-quarters of those infected in mainland China.

In California, passengers from the coronavirus-stricken Grand Princess were allowed off the vessel and walked to the bottom of a ramp, where masked officials in yellow protective gear and blue plastic gloves took their temperature and led them to a tent for more screening before they lined up to board a bus.

Authorities said foreign passengers would be flown home, while Americans would be flown or bused to military bases in California, Texas and Georgia for testing and 14-day quarantines.

After days of being forced to idle off the Northern California coast, the ship docked Monday at Oakland with about 3,500 passengers and crew, including at least 21 who tested positive for the new virus.

The evacuation of the 951-foot (290-meter) ship began Monday with several hundred people let off the ship, including more than 200 Canadians who were flown to a military base in their country, authorities said. About 2,000 passengers, including hundreds of Californians, were still aboard Tuesday morning.

“I’m bored and frustrated,” said Carolyn Wright, 63, of Santa Fe, New Mexico. “All of a sudden a two-week vacation has turned into a five-week vacation.”

About 1,100 crew members, 19 of whom tested positive for the virus, will be quarantined and treated aboard the ship, which will dock elsewhere after passengers are unloaded, Gov. Gavin Newsom said. He and Oakland’s mayor sought to reassure people that no passengers would be exposed to the public before completing quarantine.

Another Princess ship, the Diamond Princess, was quarantined for two weeks in Yokohama, Japan, last month because of the virus. Ultimately, about 700 of the 3,700 people aboard became infected in what experts pronounced a public health failure.

Rodriguez reported from San Francisco. Associated Press writers Janie Har, Jocelyn Gecker and Juliet Williams in San Francisco, Robert Jablon in Los Angeles and Rob Gillies in Toronto contributed to this report.