A woman has died in what is believed to be a mountain lion attack on a popular American hiking trail.
The woman was found lying on the ground by fellow walkers on Thursday afternoon - with one of the beasts spotted nearby.
Her death is thought to be the first of its kind in more than 25 years.
Colorado Parks and Wildlife confirmed the incident happened on the Crosier Mountain trail in Larimer County.
"Around 12.15pm this afternoon, hikers on the Crosier Mountain trail in Larimer County observed a mountain lion near a person lying on the ground from about 100 yards away," a spokeswoman said during a press conference on Thursday.
The last time someone died from a mountain lion attack in Colorado was 1999.
Wildlife officials are treating the death as a suspected mountain lion attack.
Hikers drove the animal, also known as a cougar, away after they saw it by throwing rocks at it, the spokeswoman confirmed.
PICTURED: An entrance to the Crosier Mountain trail in Colorado, where a woman has died in a 'mountain lion attack'
|"One of the witnesses is a physician," she said, adding that the doctor "did not find a pulse."
The group had been approximately 100 yards from the scene when they first noticed the mountain lion standing close to the body.
After scaring off the big cat, the doctor among the witnesses approached and checked the body for signs of life.
Authorities have now launched a probe into the suspected attack.
ANIMAL ATTACKS - READ MORE:
The discovery prompted an immediate response from wildlife officers and emergency services across the region.
Multiple agencies joined forces to search for mountain lions in the area following the discovery.
Colorado Parks and Wildlife officers, Larimer County Sheriff deputies, Estes Park police and Glen Haven Area Volunteer firefighters all responded to the scene.
A wildlife biologist conducting aerial deer surveys in the county also joined in the search, looking out for the mountain lions from above and helping transport personnel.
Mountain lion attacks on humans in the Centennial State are considered to be rare, according to wildlife officials - with only 28 attacks reported to CPW since 1990
|GETTY
Then, houndsmen brought tracking dogs to the scene in a bid to follow the scent of lions nearby.
The coordinated effort covered an extensive area around the Crosier Mountain trail where the woman's body had been found.
Officers found one mountain lion at the scene and shot it, but the animal fled before being tracked down and euthanised.
A second was discovered nearby shortly afterwards and was also put down.
It remains unclear whether one or both animals were involved in the suspected attack on the woman.
"According to CPW policies, wildlife involved in attacks on humans must be euthanized to ensure public safety," the agency said in a press release.
Pathologists will now perform a necropsy on the animals, checking for abnormalities and neurological diseases like rabies or bird flu.
Mountain lion attacks on humans in the Centennial State are considered to be rare, according to wildlife officials - with only 28 attacks reported to CPW since 1990.
According to the CPW, there are between 3,800 and 4,400 mountain lions in Colorado.
More From GB News