A Forest Lake nursing home employee repeatedly stole a powerful narcotic -- at times while off-duty -- and left a resident without her painkiller for two months, state investigators have determined.

The staff member at Birchwood Health Care Center was fired for stealing 59 oxycodone pills from the resident, according to a state Health Department report released last week. On five occasions, investigators found, she stole oxycodone during shifts when she was not working.

The state also determined that the staff member had not renewed her license to practice nursing in Minnesota.

As is practice, the employee and the resident were not identified in the Health Department report.

The case is the latest in a series of painkiller thefts that have alarmed state officials and led to the creation of a task force of health care and law enforcement officials early last year. Their review found 250 cases of prescription drugs being stolen or reported missing at Minnesota health care facilities from 2005 to 2011.

The number of reported drug thefts at Minnesota hospitals and nursing homes has more than doubled since 2005, according to the task force, and reflects what experts say is a nationwide surge of prescription-drug abuse, in many cases by health care professionals.