The number of deaths from the coronavirus reported in the U.S. jumped from six to nine in a matter of hours Tuesday — all in Washington state.

The State Health Department confirmed that eight of the deaths were in King County and that one was in Snohomish County. Washington is the only state where people have died so far.

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“This is a very fluid, fast-moving situation as we aggressively respond to this outbreak,” Dr. Jeff Duchin, health officer for Seattle and King County Public Health, said in a news release.

There are 31 cases in the state. Four of the patients were evacuated from the Diamond Princess cruise ship. But many others are associated with a long-term care facility called Life Care Center in Kirkland, a suburb of Seattle.

Sen. Patty Murray, D-Wash., heard about the uptick in the death toll while speaking at a Democratic policy luncheon in Washington, D.C., on Tuesday afternoon.

“I just was texted that two more people have been confirmed fatalities in King County in Washington state, just while we’re standing here,” Murray said. They brought the death toll to nine.

“This is truly a serious crisis,” she added.

One of the newly reported deaths was that of a person who passed away last week, on Feb. 26, after having been transferred from Life Care Center.

It may have been the first death associated with coronavirus in the country, but it was not until after the patient had died that the infection was discovered. Some staff members at Harborview Medical Center in Seattle, where the patient died, may have been exposed to the virus, according to UW Medicine, which oversees the hospital. The employees are undergoing screening.

Health officials in King County said in a news release that the level of concern has been raised particularly for “vulnerable populations such as people over 60, those with underlying health conditions or who are immune compromised.”

The statement predicted more cases in the coming days and weeks.

The demand for information has been so great that the state Health Department has established a call center to answer questions from the public.

Officials in King County said Monday that they plan to buy a local motel and to set up modular units that will isolate people who have been diagnosed with coronavirus. The modular units will be set up in publicly owned parking lots and other available land.

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Washington can now test for the coronavirus following a delay because of problems with the original test kits.

Murray expressed annoyance at the lag in ability to test.

“I am hearing from people personally across our state who are frustrated,” she said. “The failure to develop and distribute working test kits to public health agencies has really cost us valuable time.”

Also Tuesday, North Carolina reported its first case, which is directly tied to Washington. Officials said the patient had recently visited Life Care Center in Kirkland.

The North Carolina resident was said to be doing well and was at home in isolation.

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