In a rare criminal action against a senior care facility, the state’s top prosecutor has filed dozens of criminal charges against the staff and former owner of a northern Minnesota senior home where residents were allegedly beaten, robbed and denied vital medical care.

The assisted-living facility, Chappy’s Golden Shores of Hill City, Minn., had its license revoked early this year after an investigation by the Minnesota Department of Health found multiple violations of state care regulations. Local and state authorities expanded their probe following allegations that a 58-year-old resident with dementia died from brain injuries after being severely beaten by caregivers at the facility.

On Monday, Attorney General Keith Ellison’s office took the unusual step of filing more than 70 criminal counts against the former owner, managers and staff of the senior home, following a far-reaching probe that included a review of more than 1 million pages of evidence.

The charges include manslaughter, racketeering, theft, operating without a license and multiple counts of criminal neglect of vulnerable adults. Chappy’s former owner, Theresa Olson, was arrested Tuesday and faces 25 charges, including one count of manslaughter for her role in the death of a resident.

“Every Minnesotan deserves to live with dignity and respect. This does not exclude the sick and the vulnerable — it includes everyone,” Ellison said in a statement.

Nearly a year ago, state health regulators uncovered what appeared to be alarming levels of violence — including physical, sexual and verbal abuse — at Chappy’s, and repeated cover-up efforts by facility administrators. Details of the abuse spurred such outrage that senior advocates repeatedly cited them as they lobbied for broader licensing legislation that passed the Legislature this spring.

The Health Department’s swift action to shut down Chappy’s, and the far-reaching scope of the criminal charges, appear to signal a tougher stance against elder abuse by state officials, who had come under criticism for insufficient efforts to protect vulnerable adults in senior care facilities.

Ellison’s action this week is believed to be the first time in Minnesota that someone has been charged with manslaughter in connection with a death at an assisted-living facility, officials said. A Star Tribune investigation two years ago found that county prosecutors rarely charge senior care owners or their staff with criminal wrongdoing, even when residents are victims of criminal behavior such as assault, rape or robbery.

“It’s like the skies have opened, and the bad players are finally being held accountable,” said Jean Peters, president of Elder Voice Family Advocates, a volunteer coalition of relatives of abuse victims that pushed for tougher enforcement.

According to a Health Department investigation, Steven G. Nelson, a resident at the facility who had cognitive disabilities and depended on a wheelchair, was brutally beaten soon after being admitted. Investigators concluded that one staff member repeatedly punched Nelson in the face, while another held him down and a third employee watched but did not intervene. Nelson suffered internal brain bleeding and died weeks later, according to the state report and family members.

Connie Billmeier, Nelson’s older sister, was in tears Tuesday afternoon after learning of the criminal charges. “I am overjoyed and elated, and I just want all the victims and all their families to get justice,” she said.

The detailed criminal complaints paint a frightening picture of conditions at Chappy’s, a remote facility that once housed nearly 40 vulnerable residents, including people with mental and physical disabilities. Chappy’s housed residents at unlicensed and unapproved facilities, including one with “visible water damage and rodent nests and feces,” according to the criminal complaint.

One resident, a 72-year-old veteran of the U.S. Marine Corps, died last year of septic shock, an untreated urinary tract infection and other complications which allegedly resulted from improper medical care and neglect.

Ellison’s office also alleges that Chappy’s had no registered nurse on staff to oversee services provided to residents, some of whom required round-the-clock care. To disguise this violation, the charges say, the facility submitted fraudulent licensing applications using the identity of a registered nurse who no longer worked at Chappy’s and forged the nurse’s signature on records, including the records of the military veteran who died from neglect.

All told, 10 people associated with Chappy’s — including the former owner, managers and employees — have been criminally charged in Aitkin County District Court. Several of those charged are relatives of Olson, the former owner, who is charged with second-degree manslaughter and of bilking the state’s Medicaid program of more than $2.1 million by billing for health services that were not covered.