ONTARIO — An inmate serving time for robbing a Portland check-cashing store and severely beating a clerk was found unresponsive in his cell at the Snake River Correctional Institution in Ontario.

Oregon Corrections Department spokeswoman Jennifer Black says 28-year-old Michael Hagen was found about 10 a.m. Thursday and sent to a nearby Boise, Idaho, hospital. Late Thursday afternoon, Black said she could not discuss what might have happened to him and did not know his condition.

One housing unit at the prison was put on lockdown “to ensure the safety of all staff and inmates.” About 80 inmates live in that unit.

Oregon State Police are investigating. Lt. Gregg Hastings said late Thursday he had no details to share on the investigation.