On the first day of April, five workers and one patient in the District’s only public psychiatric hospital had tested positive for COVID-19, the disease caused by the new coronavirus.

Fifteen days later, four patients at Saint Elizabeths Hospital were dead after becoming sickened by the virus, and nearly 80 other patients and workers tested positive for the disease, according to court papers filed in the U.S. District Court for the District of Columbia on Thursday.

Four patients represented by the Washington Lawyers’ Committee for Civil Rights and Urban Affairs say the city-owned hospital is putting patients at risk for contracting the coronavirus by not isolating people who have symptoms.

They also argue it is impossible for patients to follow social distancing guidelines that public health experts say are necessary to keep the virus from spreading, and allege that patients with the disease are not given adequate care.

Officials with D.C.’s Department of Behavioral Health, which oversees St. Elizabeths, did not immediately respond to questions Thursday night.

Last October, the patients filed a class action lawsuit against St. Elizabeths after spending nearly a month without clean, running water. They amended the lawsuit this week to include details about the hospital’s response to the coronavirus pandemic, arguing the facility has not done enough to avoid another emergency.

Kaitlin Banner, the deputy legal director at the Washington Lawyers’ Committee, says the facility serves a large population of people of color, many of whom live in poverty.

“This is the second time in a short number of months where there has been a public health emergency that has affected St. Elizabeths Hospital,” Banner says. “From everything that we’ve learned, the conditions that that has resulted in for patients are just horrific.”

One patient, Stefon Kirkpatrick, said in court papers that he had a fever, cough and shortness of breath—symptoms of COVID-19. Kirkpatrick said the hospital did not test him for the virus after he reported the symptoms in early April.

The lawsuit alleges the 30-year-old, whose symptoms have since improved, was not isolated from other patients or asked to self-quarantine. Kirkpatrick said he was directed to stay in his unit, which houses 26 men.

The patients suing the hospital say it is impossible to maintain a six feet distance from others, nor have they been provided masks or other protective equipment. The lawsuit says the hospital is testing patients who show coronavirus symptoms but not those who may have been exposed to others with the virus.

The documents say patients are “at a heightened risk of contracting, and are, in fact, dying from COVID-19,” because of the hospital’s “failure to follow professional guidance and appropriately plan.”

The Washington Lawyers Committee, which is also working with the D.C. chapter of the American Civil Liberties Union and the law firm of Arnold & Porter, is urging the city to reduce the population at St. Elizabeths.

They also want to ensure the hospital is following testing and safety guidelines from the Centers for Disease Control that apply to places such as nursing homes and other long term care facilities.

St. Elizabeths is located in a 450,000-square-foot building in Southeast. It provides intensive care for people with serious mental illness, and conducts mental health evaluations for patients committed by the courts.

This story originally appeared on WAMU.