Seven people, most of them children, have died after being infected with a virus at the Wanaque Center for Nursing and Rehabilitation, New Jersey health officials said Wednesday.

The victims were among 23 "medically fragile" patients to be infected with a type of adenovirus at the facility in Haskell, Passaic County, the state Department of Health said. Four of those 23 were added to the total on Friday after confirmation by lab test.

A state inspection team was on site Sunday, finding "minor handwashing deficiencies," and the facility has been ordered not to admit new patients until the outbreak ends.

Adenoviruses can cause mild to moderate symptoms in many patients. But the strain of virus in this outbreak, known as No. 7, causes severe symptoms, and patients at the facility already suffered from compromised immune systems before becoming infected, the state said.

Six of the deaths were confirmed by health officials on Tuesday. State officials said they learned Tuesday night that the seventh person had died after being hospitalized; that death was announced Wednesday morning. All seven were described as pediatric residents, though at least one was as old as 22 — the upper limit for how the center defines "pediatric," according to the Associated Press.

State health officials said they were continuing to investigate the outbreak with assistance from the U.S. Centers for Disease Control and Prevention.

On Tuesday, Gov. Murphy said state Health Commissioner Shereef Elnahal had ensured the facility was undertaking "enhanced" measures to prevent further illness.

"I am heartbroken by the news that several children have lost their lives in an adenovirus outbreak at the Wanaque Center for Nursing and Rehabilitation, and pray for the full recovery of the other children impacted," Murphy said in a statement. "I am confident that the steps being taken by state and local officials will minimize the impact to all those who remain at the facility, including patients and employees."

The 227-bed for-profit facility cares for gravely ill children and adults, many of whom use wheelchairs and must breathe and eat via tube.

The center notified the state about a potential outbreak on Oct. 9, Elnahal told the AP. Inspectors were on site 11 days later, the AP said.

The Health Department also visited the site in August for a routine inspection and issued six citations, according to Medicare's Nursing Home Compare website.

Among the findings in an August site visit was old, mildewed carpet on the fourth floor, causing a "strong unpleasant odor" that was "pervasive throughout the entire floor," inspectors wrote.

Inspectors also found a hole in a urinary drainage bag in one patient room. Staff had placed a receptacle beneath the bag to catch leaking urine, and were unable to say how long the hole had been there, inspectors wrote. Asked about the leak, a nurse said that "supplies were not the best," state inspectors wrote.

Staff also failed to clean and trim the fingernails of one resident who was totally dependent on others for personal hygiene, causing "redness on the palm from the long nails pushing into the skin," inspectors wrote.

They issued a rating of "below average" — two stars out of five — in their Aug. 20 report.

This article was updated Friday to reflect the confirmation of four additional infections, bringing the total to 23. It contains information from the Associated Press.