A 36-year-old woman, working as a head keeper at Oregon's WildCat Haven Sanctuary, was killed by a big cat Saturday evening, after she entered the cage alone.

The victim, 36-year-old Renee Radziwon, was attacked and killed by a cougar at the WildCat Haven Sanctuary. Radziwon was a trained animal caretaker and worked as the head keeper at the Oregon sanctuary for nearly a decade.

According to the investigators, Radziwon was alone in the wildcat cage during the attack, which took place around 7 p.m. local time Saturday. She was found dead when the first responders arrived at the scene.

"Right now, our thoughts and prayers are with the family of our dear colleague and friend who we have so sadly lost," executive director Cheryl Tuller, said in a press release. "We are devastated by this loss. Not only was she one of our most dedicated staff members, we thought of her as family. We send our most heartfelt prayers to those she has left behind."

The WildCat haven is a non-profit, no-kill, "last hope" sanctuary located on 8 acres of land in Sherwood, Oregon. It provides a natural habitat for captive-born wildcats. The area is enclosed on all sides with "14-foot tall walls of six-gauge wire, with secure ceilings, lockout areas, and double-door entries." The sanctuary guarantees the safety of the neighbors and has taken extreme precautions as required by the U.S. Department of Agriculture. It has also been verified and accredited by the the Global Federation of American Sanctuaries (GFAS) and the American Sanctuary Association (ASA).

The organization regretted the loss of their employee, but emphasized that the tragedy highlighted the violation of an important rule, which states "two qualified staff members shall work together during the lockout of dangerous animals," according to Tuller. "Once the animals are locked out, one staff member can safely enter the enclosure to clean or make repairs. Two qualified staff members shall be available when releasing animals from lockout areas."

The Sanctuary, founded by Cheryl and Mike Tuller, was started in 2001. The organization's efforts have resulted in the rescue of more than 60 neglected, abused, captivated wild cats. The sanctuary is a home for wild cats such as tigers, bobcats, cougars, and lynx and is not open for public.