The state launched an investigation Monday into an inmate trusty’s attack on an official at the Swan River Correctional Training Center.

Donna Weeks, administrative assistant, remained in critical condition Monday after being assaulted Sunday night, state corrections officials said.

Weeks was unconscious with head and neck injuries at the Kalispell Regional Hospital, said Sally Johnson, deputy director of the Department of Corrections and Human Services.

She identified the suspect as Rodney Sattler, 27, of Thompson Falls. He was taken to the Lake County jail in Polson.

Lake County Attorney Kim Christopher said Sattler will be arraigned later this week, but she declined to speculate on what charges may be filed.

Johnson said the department launched an investigation into the incident Monday morning, but officials did not have a motive for the assault.

She said the attack apparently occurred about 7:30 p.m. in a bathroom of the administration building where Weeks worked and was temporarily living.

Another trusty walking outside the building heard Weeks’ screams and ran inside where he found Sattler and Weeks in the bathroom, she said. Weeks was lying injured on the floor.

Sattler allegedly grabbed the man’s throat, pushed him aside and ran from the building, Johnson said. Lake County Sheriff Joe Geldrich said the suspect ran from the unfenced camp and turned himself in to a state forester nearby.