PORTLAND, Ore. (AP) — The estate of a young woman who was mauled to death by a cougar while working at a wild-cat sanctuary in suburban Portland is suing the sanctuary and its owners.

The lawsuit against WildCat Haven and owners Michael and Cheryl Tuller alleges the sanctuary is liable for the death of Renee Radziwon-Chapman because she was left alone with the animals despite expressing concerns about working solo.

The 36-year-old animal keeper was found dead inside the animals’ enclosure in November 2013, with two cougars roaming freely near her. She had been working at the sanctuary for eight years. Investigators say it was likely she was cleaning the enclosure when she was attacked and killed.

The lawsuit was filed last week in Multnomah County District Court.

Radziwon-Chapman’s estate seeks $6 million in damages for wrongful death, ultrahazardous or abnormally dangerous activity, intentional misconduct, employers’ liability law, and violations of the Oregon Safe Employment Act.

The suit says the beneficiaries of Radziwon-Chapman’s estate include her husband, Aaron Chapman; baby daughter, Noa Elise Chapman; mother, Carol Radziwon; and father, John Radziwon.

The Tullers did not return a call seeking comment.

After Radziwon-Chapman’s death, her mother Carol Radziwon had told The Associated Press the young woman had expressed concerns about safety measures at the facility.

According to the lawsuit, Radziwon-Chapman had worked alone at the sanctuary the day of her death, as well as the day before. It says the keeper sent a text message to co-owner Cheryl Tuller the day before her death expressing concerns about working solo with the animals.

“Tuller reassured her that she would not be left alone with the cats, which would be a violation of WildCat Haven’s protocols, both written and oral,” the lawsuit says.

The sanctuary’s protocol calls for two qualified workers inside an enclosure containing animals.

Despite the protocols and Radziwon-Chapman’s concerns, the suit says that on Nov. 9, both the sanctuary owners and another employee who usually worked with the head keeper were not present at the facility — they were working at another property in another county, where the Tullers plan to eventually move the sanctuary.

The lawsuit says Michael Tuller “intentionally instructed” the keeper to work in the cages alone with the animals, in violation of the sanctuary’s protocols.

The lawsuit also says WildCat Haven failed to maintain adequate locks on the doors to the cages of the wildcats and that the gate did not latch properly.

In June, the sanctuary agreed to pay $5,600 in penalties as part of a settlement with the Oregon Occupational Safety and Health Division.

The state agency had found that WildCat Haven violated its two-person safety procedure by allowing employees to work alone with the wild cats on a frequent basis. The OSHA investigation cited the cellphone messages sent by Radziwon-Chapman as part of its investigation.

Investigators also said the latches on a smaller cage where cougars were locked out of the larger enclosure were inadequately designed. The “light duty substandard gate latch” was designed for easy operation in backyards, but it was “inappropriate for securing dangerous cougars,” investigators wrote.

To secure those inadequate latches, workers had to enter the large enclosure and hook a carabiner over each latch. “In doing so,” OSHA said, “they were exposed to cougars who were housed in a lockout that was not fully secured.”

The sanctuary said it had addressed the state’s safety concerns.

WildCat Haven is a nonprofit that rescues wild animals such as cougars, bobcats, tigers, and other wild cats. It currently houses about 65 animals. The sanctuary is 17 miles south of Portland, in a secluded, wooded area. It is closed to the public but can conduct tours for donors.