An Oregon man who once pleaded guilty to attempted murder and is suspected of stabbing his mental health caseworker to death during a home visit remained in a Portland hospital's intensive care unit after suffering knife wounds to his neck.

Brent Redd, a 30-year-old who pleaded guilty except for insanity to a charge of attempted murder in 2007, was under supervision by the nonprofit Columbia Community Mental Health.

St. Helens Police Chief Steve Salle said Monday that dispatchers received a call at about 8 a.m. Sunday, directing them to Redd's home on a report of a disturbance. They then received more calls indicating that there had been a stabbing.

Salle said Redd answered the door and ran. He was detained after a short chase. Inside his house, Salle said police and medics found the body of Jennifer Warren.

According to a joint statement released by the Columbia County nonprofit and the Oregon Psychiatric Security Review Board, Redd had been under the jurisdiction of the review board since his guilty plea in 2007. Redd was sentenced to the Oregon State Hospital for 20 years but was given conditional release in September 2010. At that time, he began receiving local community treatment and remained under the board's care.

"Our thoughts and prayers are with the family and friends after this terrible incident," Columbia County Mental Health said in a statement Monday. "We are working closely with the proper authorities and have initiated an independent review to ensure the safety of our mental health workers."

Columbia County District Attorney Steve Atchison said Monday that he's unable to file charges until Redd is released from the hospital.

Atchison and Salle said they do not remember being notified of Redd's presence in the community. He was charged and pleaded guilty to attempted murder in Wasco County, which is about 130 miles southeast of Columbia County.

Atchison and Salle said they may have been notified, but neither recalled it or had paperwork reflecting their notifications.

"That doesn't mean I wasn't notified, but I'm not aware of any notification," Atchison said.

The stabbing reportedly occurred as Warren was conducting a scheduled visit with Redd.

Warren's death was the first time in 34 years that any client under the Psychiatric Security Review Board's jurisdiction has been accused of "a violent act of this nature."

Officials said there are currently 615 people under the Psychiatric Security Review Board's jurisdiction, and 415 of those are under conditional release within the community. Since 1978, the Psychiatric Security Review Board has overseen more than 1,400 people who have been found guilty except for insanity "with a recidivism rate of 2 percent," the statement said.