Since 1998, when a D.C. Superior Court judge found Eric Izlar not guilty by reason of insanity of an aggravated assault charge, he has been a patient of St. Elizabeths Hospital, the District’s psychiatric institution.

But about 4:30 p.m. Dec. 18, while Izlar was sitting outside with a hospital employee, he walked away and “jogged” out of the hospital gate, according to a letter to the court from the hospital.

Izlar, 42, who has nearly a half-dozen arrests on charges including burglary, robbery and assault, headed toward Alabama Avenue in Southeast.

Since then, authorities have been quietly searching for Izlar. Officials at the city-run hospital said they alerted D.C. police and hospital security. The U.S. Marshals Service said a warrant has been issued to pick up Izlar and return him to the hospital.

What makes Izlar’s case more troubling is his history of violence. In 2010, he was charged with assaulting a hospital staffer with a deadly weapon. He served a two-year sentence before returning to the hospital.

Eric Izlar (Courtesy U.S. Marshals Service)

Izlar has received a diagnosis of schizoaffective disorder, bipolar disorder, antisocial personality disorder and substance dependence, court papers said. It’s unclear whether Izlar has been taking his medication since he left the hospital, and in the letter to the court, officials from the hospital warned: “Of import, Mr. Izlar has a history of threatening and seriously assaulting staff members at [the hospital] and in the community, particularly when non-compliant with treatment.”

This was not the first time Izlar fled the grounds. In 2007, Izlar left the hospital, and federal marshals found and returned him, court records say. Izlar was included in a 2005 Washington Post article about criminally insane patients who were learning a trade at the hospital.

Last week, Daniel Ellis, 56, who had voluntarily committed himself to the hospital, was found dead under a pile of snow after he walked off the property. Ellis left the hospital without obtaining a proper discharge, officials said.

Phyllis Jones,of the D.C. Department of Behavioral Health, which oversees St. Elizabeths, said patients sometime walk off campus. “It happens usually about once a month,” Jones said. But the patients usually return, either on their own or after the marshals find them, she added.

Mayoral candidate and D.C. Council member Tommy Wells (D-Ward 6) called the recent cases “troubling.” Wells, who oversees the city’s Public Safety Committee, said he is concerned about the patients’ health and the community’s safety when patients slip away. “It sounds like a breakdown and a failure of St. Elizabeths,” he said. “Once a month is not acceptable.”

Jones said Izlar was assigned one staff member and was permitted to sit outside because he had shown signs of improvement.

“There is a lot of conversation in the community as to how to best treat people with a mental illness,” Jones said. “The goal is to help them integrate back into the community. We continually evaluate people to see if they are getting better. As they get better, we gradually give them more privileges to see if they can handle their freedom.”

Marshals asked anyone with information to call 202-307-9100.