In the Oregon case, WildCat Haven in Sherwood said its head keeper, Renee Radziwon, 36, of Portland, broke a safety protocol that calls for two qualified workers in an enclosure with animals.
But Radziwon's family says the woman did not break any rules and had expressed concerns about working alone just days before the attack.
What exactly occurred may never be known, because there are no cameras at the facility. But the circumstances of Radziwon's mauling recall the March death of 24-year-old Dianna Hanson at Cat Haven in central California. Hanson was also killed while cleaning an enclosure.
Hanson died after one of two lions escaped from a smaller feeding cage into the enclosure and attacked her. She, too, was working alone — though another worker at the facility was in contact with her via walkie-talkie.
In that case, authorities concluded that proper enclosures were in place and the intern had committed a fatal error: She failed to secure the latch of a door to the smaller cage.
Authorities in the Oregon case have directed no blame. The Clackamas County Sheriff's Office said Monday that it had finished looking into the attack and concluded no crime was committed.
The state Occupational Safety and Health Administration and the U.S. Department of Agriculture are still investigating.
WildCat Haven owner Michael Tuller discovered Radziwon bloodied and lying on her back inside the enclosure at about 7 p.m. Saturday and pulled her body by the boots into a secure entrance before calling 911.
According to a Clackamas County sheriff's report, responding officers found one cougar walking freely inside a main enclosure with a small amount of blood above its nose, and a second cougar in an enclosed 15-by-15 cage.
Tuller told authorities that Radziwon was alone at the facility because he and his wife — the sanctuary's executive director, Cheryl Tuller — were at another property in Scotts Mills, where they plan to eventually move the sanctuary, the report said.
The sanctuary said in a statement Sunday that the facility's handbook specifies that a staff member can enter an enclosure to clean or make repairs only after the animals are locked out of it.
The enclosure is surrounded on all sides with a 14-foot wall of thick wire with secure ceilings and includes a lockout area and double-door entry, according to the statement. Tuller told investigators he found Radziwon's body about 10 feet away from the inside door.
Sheriff's officials did not say whether Radziwon disregarded the safety protocol and allowed one of the cougars out into the enclosure with her, whether she left the smaller cage unlatched, or whether the cougar had escaped from the smaller cage as the lion did in California.
The sanctuary did not return multiple calls for comment Monday.
Carol Radziwon said her daughter was very careful around the animals and would not break any safety rules, because she had written some of them herself.
"There was no one there to help her. There was no one at that sanctuary. They left her completely alone," Carol Radziwon told the Associated Press by phone from Pennsylvania.
Autopsy results released Monday showed Renee Radziwon died at the scene of multiple bite wounds concentrated on her head and neck.
It was not immediately clear whether the cougar that attacked her would be put down. In California, sheriff's deputies killed the lion when they could not lure him away from Hanson's body.
The USDA is looking into the Oregon incident to determine whether any noncompliance with the Animal Welfare Act contributed to the attack, spokeswoman Tanya Espinosa said. As in the California case, USDA investigators will look at whether proper enclosures were in place and whether they were in good working order.
Two routine inspections conducted by the federal agency at the Sherwood sanctuary in 2011 and 2012 showed no violations, according to USDA records.
Oregon OSHA will also investigate the sanctuary's safety protocols and safety training, spokeswoman Melanie Mesaros said.
WildCat Haven is a nonprofit that rescues captive-born cougars, bobcats, tigers and other wildcats. Cougars are the size of large dogs and are native to the American West.
The sanctuary is 17 miles south of Portland, in a secluded, wooded area. It's closed to the public, but conducts tours for donors. The Tullers opened the facility in 2001 and still run it. Its website says the sanctuary houses more than 60 cats. Renee Radziwon was the only staff member listed on the site.
Renee Radziwon, who was originally from Philadelphia, leaves behind a husband and 5-month-old daughter.
Officials at another big cat sanctuary, Big Cat Rescue in Tampa, told The Associated Press last year that at least 21 people, including five children, have been killed and 246 mauled by exotic cats in the U.S. since 1990. Over that period, 254 cats escaped and 143 were killed.
Contact Gosia Wozniacka at https://twitter.com/GosiaWozniacka
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