The Maryland prison system reported its first confirmed cases of coronavirus Monday, with one inmate and two contract employees testing positive at two separate facilities, while health officials confirmed a separate outbreak at the state’s maximum security psychiatric hospital.

The cases follow weeks of warnings from advocates that the highly contagious virus could be catastrophic if it is able to get behind the walls of such secure facilities.

The three prison system cases are associated with correctional facilities in Baltimore and Jessup, officials said. They did not immediately specify which facilities were affected or how the system was conducting tests, if at all.

“The Department of Public Safety and Correctional Services has COVID-19 Response Teams working to determine whether any other staff or inmates may have had contact with the three individuals who tested positive,” corrections spokesman Mark Vernarelli said.

A corrections officer and union shop steward at the Jessup Correctional Institution said the state has been keeping information from its officers.

“The department gave us no information at all; everything we have found out is through word of mouth from officer to officer,” said Oluwadamilola Olaniyan. “They are still not screening all people entering the jail from all entrances, and they have removed the medical staff that were providing the screening — now [corrections officers] are doing it. And we have no idea what the department’s plan for handling another inmate or employee who is infected.”

Gov. Larry Hogan, who said two weeks ago that inmates would be “safer where they are,” said Monday that he was concerned about the virus spreading to “literally thousands” of facilities in Maryland, to include hospitals, detention centers and nursing homes.

Advocates for prisoners and medical experts have been calling on the state to implement procedures to safeguard inmates and to thin the prison population. Hogan’s office has said it was taking the concerns under advisement.

“This is a very complex issue involving many agencies, the courts, and the federal government,” Vernarelli said.

Vernarelli said the department has been deep-cleaning its facilities for days and has identified locations and spaces within its facilities for isolation and quarantine. Inmates are being given extra soap free-of-charge, he said, and the system has “canceled visits, modified inmate movements and implemented grab-and-go meals where possible.”

“We’re stressing health information and personal hygiene for both employees and inmates and detainees,” Vernarelli said. “Temperature checks and health questionnaires are being administered to staff at every shift change.”

Leonard Rubenstein, a program director for the Center for Public Health and Human Rights at the Johns Hopkins Bloomberg School of Public Health, said the confirmation of cases is evidence that swift steps must be taken to reduce statewide prisoner populations.

“These cases underline the urgency for the governor to take action very, very quickly. If people don’t get out, it will spread very quickly and make it difficult to create the space to protect inmates and staff from infection,” Rubenstein said.

“We can unfortunately expect rapid spread if the population is not reduced.”

Lauren-Brooke Eisen, director of the justice program at the Brennan Center for Justice at New York University School of Law, said there needs to be a push across the country for more elderly people with health issues and offenders who are no longer a threat to society to be released.

“We are worried about all the people behind bars, especially those 50 or older and those who may have health problems,” Eisen said. “We are worried about the deaths that we may start to see behind bars; we know how quickly they spread. We are urging more released for people across the country.”

Maryland has not disclosed any considerations regarding potential acceleration of releases, even as court hearings and parole hearings have been cancelled due to coronavirus concerns.

The state prison system also runs Baltimore’s Central Booking facility. Baltimore State’s Attorney Marilyn Mosby instructed prosecutors to reject low-level arrests brought by police such as for drug possession, prostitution and open container violations, though people arrested for those crimes were unlikely to be detained in the first place.

Mosby also joined defense attorneys, medical professionals and others calling for Hogan to release certain older, immuno-compromised and parole-eligible prisoners.

Mosby’s office on Monday reiterated the push for Hogan to establish a plan for reducing prison populations and preventing spread of the virus. In a statement, the office says there needs to be a comprehensive plan on handling prisons and COVID-19.

“Today’s news confirming the first coronavirus cases in Maryland prisons underscores that now, more than ever, the Governor must immediately formulate and implement a comprehensive plan for safely handling prisons and COVID-19,” Mosby said in a statement. “I, along with public health officials, public defenders, and criminal justice experts have provided detailed proposals to Governor Hogan and still stand ready to assist him in any way to prevent the spread. The clock is ticking and we must act now to protect the public’s health.”

Wendy Marshall, who says her son is being held at the Metropolitan Transition Center in Baltimore, says he told her Monday that two inmates being held in the same area as him are symptomatic.

“One inmate was having difficulty breathing, fever and very sick,” Marshall told The Baltimore Sun. “Trials are not being furthered by the State’s Attorney’s Office until further notice, leaving many innocent men in this death trap for several months.”

Meanwhile, the maximum-security Clifton T. Perkins Hospital in Howard County was dealing with its own outbreak. The facility provides treatment to people who are arrested and referred for evaluation, or deemed not criminally responsible or incompetent to stand trial.

Health officials confirmed Monday that eight patients and one staff member had tested positive for COVID-19, and they were working with Howard County’s health department.

Charles Gischlar, a spokesman for the state health department, said Perkins is not permitting visitation to the facility and staff who are sick “may not report for work.” He said all staff and patients are being required to wear masks, and patient temperatures were being taken twice a day.

“All units are following strict isolation precautions, and movement within the hospital is limited,” Gischarl said.

Patrick Moran, president of AFSCME Council 3, which represents some of the employees inside the facility, told The Sun that the outbreak at Perkins was indicative of a larger issue with how the state is handling some essential employees.

“We have been warning the administration about this happening for weeks,” Moran said.

Sun reporter Phil Davis contributed to this article.