A missing hiker whose body was found Monday in Oregon was likely killed by a cougar — the state’s first fatal attack by the big cat in the wild, authorities said.

The body of Diana Bober, 55, of Gresham, was found off the Hunchback Trail in the Mt. Hood National Forest in Welches by search and rescue teams with the Clackamas County Sheriff’s Office. Bober, an avid hiker who was last seen on Aug. 9, was reported missing on Friday, sheriff and wildlife officials announced Tuesday.

“This is a terrible tragedy, and our sympathy goes out to Diana’s family and friends,” Brian Wolfer, watershed manager for the Oregon Department of Fish and Wildlife, said in a statement. “All of us at ODFW are thinking of you today.”

Bober’s body had injuries consistent with a suspected cougar attack, according to Sgt. Brian Jensen of the Clackamas County Sheriff’s Office. DNA samples collected at the scene have been flown by Oregon State Police to the US Fish and Wildlife Service Forensics Laboratory for further analysis and positive identification of the animal responsible for the fatal attack, Jensen said.

Her death marks the first verified fatal attack by a wild cougar in Oregon. Wildlife officials are now working to locate and kill the cougar, one of roughly 6,600 cougars throughout the state. The animals, which are known to damage crops and kill livestock or pets, prompt about 400 complaints to wildlife officials each year, Jensen said.

“This is an unprecedented event in Oregon, we are asking people to avoid this area while we attempt to remove this cougar,” Wolfer’s statement continued. “We don’t know what risk it poses to the public.”

Anyone who sees a cougar in the area where Bober was found was advised to call authorities. Hikers were also advised to travel in groups, to make noise to alert animals to their presence and to be particularly alert at dawn and dusk, when cougars are especially active.

Officials warned that anyone who encounters a cougar should not run. Maintain direct eye contact and back away slowly while raising your voice and speaking firmly. If the animal appears aggressive, wildlife officials suggest raising your arms to appear larger while clapping your hands.

The last fatality caused by a cougar in Oregon took place in 2013, when an animal keeper at a large cat sanctuary near Sherwood was mauled while cleaning an enclosure, The Oregonian reports. More recently, a man was killed by a cougar while mountain biking in Washington state in May.

Bober’s relatives, meanwhile, said she regularly hiked near Mount Hood and the Columbia River Gorge.

“She would go hiking several times a week,” Diana’s sister Alison Bober told the newspaper. “She was very independent and always felt very safe on the trails.”

Diana Bober apparently tried to fight off the animal that attacked her, her sister said.

“Although she died of her wounds, the wild animal didn’t come back to her,” Alison Bober told the newspaper.

A memorial service for Diana Bober was not yet planned, but her sister suggested that people head outdoors to the “natural world” in her memory.

“She would say you have to live your life without fear,” Alison Bober told the newspaper. “Nothing in life is truly safe. That’s what she would want, just for people to enjoy the important things in life such as a day of beauty.”