A staff member at the state-run sex offender treatment facility in Moose Lake was attacked and seriously injured by a resident with a long history of violent outbursts there, officials said.

The assault occurred early Monday afternoon, and the 29-year-old suspect was arrested and awaits possible felony charges, according to the Minnesota Department of Human Services.

The agency said the resident ambushed a 53-year-old staff member from behind without provocation with a heavy object, and kept up the assault by beating and kicking his victim as others who work there came to their colleague's aid.

The staffer, who was making his scheduled rounds at the time, was taken by air ambulance to a hospital for treatment. His condition has yet to be disclosed. The agency did not release his identity.

Carlton County sheriff's deputies responded and arrested the resident. He's being held on suspicion of second-degree assault with a dangerous weapon and fourth-degree assault in a secure treatment facility, according to the jail roster. The Star Tribune generally does not identify suspects before they are charged.

Nancy Johnston, executive director of the Minnesota Sex Offender Program, said in a statement Monday, "We are deeply disturbed by such a brutal, senseless attack. I'm grateful to those who tried to intervene and protect our coworker. Our hearts are with him and his family, and we'll be there to support him as he recovers."

The resident has numerous convictions for violent outbursts at the Moose Lake facility, according to court records:

  • In June 2020, he was handcuffed while he kneed and bit a staff member.
  • In March 2019, he put a hairbrush in a sock and swung it at various objects, hit doors, damaged windows and yelled death threats at staff during a 20-minute tirade.
  • In June 2017, he punched and kicked a security counselor into unconsciousness.
  • In May 2016, he spit and attacked a security counselor, broke a table tennis table and threw a chair at a television.

The court order for the suspect's indefinite commitment into the sex offender program said the suspect became sexually active before turning 10 years old, and was charged as a teenager for sexually abusing a 9-year-old boy and later molesting a female staffer at a Dakota County group home.

The Department of Human Services said it has begun its own review of this latest incident and cannot otherwise comment on any specifics about the attack.

Agency spokesman Christopher Sprung said sex offender program residents are not locked in their rooms and are afforded "varying levels of liberty. The unit where clients live and their freedom to move about the campus is based on behavior."

Sprung said that residents who do not cause trouble "can leave their rooms in the morning and go about their day — meals, recreational activities, religious services, individual and group therapy sessions, jobs — mostly self-directed and return to their units by an appointed time in the evening."

The program also operates two small "behavioral units for clients who are exhibiting problem behaviors," he said. "The four-room units are staffed differently and are more intensely monitored."

These residents cannot leave their units except for certain circumstances, medical appointments, for instance, and must be escorted. Behavioral units are intended for short-term stays while a plan is implemented to get the residents back on track so they can eventually return to the traditional units.

There are also high-security areas, which are single rooms for residents who have lost "behavioral control or [were] involved in serious incidents like assaults on staff or other clients."