At a New York City hospital in the center of the state's coronavirus outbreak, at least 13 patients died in the span of 24 hours, hospital staff said.

Elmhurst Hospital, part of the city's public hospital system, said in a statement that the 13 deaths were consistent with the number of intensive care unit patients the hospital was treating at the time.

The deaths occurred from Tuesday to Wednesday at the Queens hospital as New York continues to battle COVID-19, the disease caused by the new coronavirus.

As of Wednesday evening, the city said it had 20,011 known cases, leading to 280 deaths.

"Elmhurst is at the center of this crisis," the hospital statement said. "It's the number one priority of our public hospital system right now."

Medical staff are working to meet the hospital's growing demand as it increases its effective capacity daily, the hospital said. Staff is doing "doing everything in our power" to save every COVID-19 patients, the hosptial added.

"The frontline staff are going above and beyond in this crisis, and we continue surging supplies and personnel to this critical facility to keep pace with the crisis," the statement said.

The New York Times reported that some patients waiting for a bed at the 545-bed facility died in the emergency room, and a refrigerated truck sits outside to hold bodies.

"It's apocalyptic," Dr. Ashley Bray, 27, a general medicine resident told the Times.

Elsewhere, the city’s convention center is being turned into a temporary hospital, and a makeshift morgue was set up outside Bellevue Hospital in Manhattan.

Earlier this week, White House officials warned that anyone who had traveled to the city in recent days should self-quarantine for two weeks after their departure.

Gov. Andrew Cuomo said the city's density and it being an international destination is what made such a hotbed for the outbreak.

“Our closeness makes us vulnerable,” he said. “But it’s true that your greatest weakness is also your greatest strength. And our closeness is what makes us who we are. That is what New York is.”

The governor has ordered everyone to stay at home "to the maximum extent possible" and banned all nonessential gatherings "of any size for any reason."

Cuomo has also said that the state has an adequate supply of masks and other protective equipment to last several days, but that the race to acquire respirators remained critical. He said they will be returned to states who donate them – and that his state will provide expertise on treatment as well.

"We are asking the country to help us," he said. "We will return the favor."

In a tweet, Mayor Bill de Blasio said the city had received 400 ventilators from the Federal Emergency Management Agency, and expected an additional 2,000 by the end of the week.

"Those WILL buy us time. But we need 15,000 — and we need them FAST," he tweeted, urging more federal help.

Earlier this week, President Donald Trump was critical of Cuomo, saying the governor should have ordered more ventilators years ago. However, Democrats have pressed Trump to invoke the Defense Production Act to require companies to expand production of the equipment.

Social distancing has helped slow the rate of New York's hospitalizations, but they are still rising above expectations, Cuomo said.

New York will need 140,000 hospital beds, almost three times the existing capacity, according to Cuomo, who said he expects the state's curve to hit its apex in two or three weeks.

"We are still on the way up the mountain," he said.

Contributing: Jorge L. Ortiz, John Bacon, Grace Hauck, Lorenzo Reyes and John Fritze; The Associated Press

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