A Colorado woman who was out on a jog in a rural area near Boulder was "attacked" by a herd of cows and hospitalized, according to a witness. 

"I just saw a runner get attacked by a herd of cows, and they’re not moving. The cows are surrounding them," witness Vivian Kuenn said in a 911 call, according to KUSA. 

Kuenn was out for a bike ride last Tuesday on Coalton Trailhead in Boulder County when she witnessed a herd of roughly 30 cows swarm and trample a female jogger. 

"Just hop on there. Get a little ride in before work, and next thing you know, see something you weren’t expecting," Kuenn said of her bike ride.

VIDEO SHOWS WRANGLERS 'COMPARABLE TO THE CAST OF YELLOWSTONE' CHASING ESCAPED COW ALONG MICHIGAN'S I-75

Colorado trail entrance

Entrance to Coalton Trailhead in Superior, Colorado.  (Google Maps )

Kuenn said she called 911 upon witnessing the attack, and feared that she witnessed the unidentified female jogger's death. 

"She screamed and was just down on the ground while they were just trampling her. In a very short span of time, she stopped moving. At the time, I was like, ‘Oh my gosh, did I just watch her die?’ Which, thankfully, wasn’t the case," she said.

Boulder County Parks and Open Space told KUSA that the female jogger was taken to the hospital for undisclosed injuries. 

"It has definitely put a sense of ‘I am going to be very, very cautious now around any cows I do see grazing,’ if they are near me," Kuenn said.

Cows in Colorado

Cows and calves herded by to pasture after branding near Boulder, Colorado  (REUTERS/Rick Wilking (UNITED STATES))

Mike Foster, agricultural resources division manager for Boulder County Parks and Open Space, told 9News that cows can be aggressive during calving season and that cows can perceive humans as a threat if they approach them quickly. 

HERD OF COWS AID NORTH CAROLINA POLICE PURSUIT, LEADING THEM ‘DIRECTLY’ TO SUSPECT 

"Livestock can be very aggressive during calving season, and we are in calving season," Foster said. "Just like a momma bear elk or moose, a momma cow is going to be very protective of its young. And when they perceive a threat they are going to react to that threat."

Colorado field

Field in Superior, Colorado, near Coalton Trailhead.  (Google Maps )

Kuenn said the female jogger was on the path at the time of the attack, and was not approaching the cattle in their pasture. 

PETA CALLS CLIMATE CHANGE PLAN THAT CULLS 200,000 COWS 'RIDICULOUS': 'GOVERNMENT KILL SQUADS' WON'T HELP

A review of Boulder County Parks and Open Space's Facebook page shows that other trails in the area were shut down this month over aggressive cattle, but have since reopened after the cattle were moved. 

CLICK HERE TO GET THE FOX NEWS APP 

It was the second cow attack in Boulder County this month, according to CBS Colorado, following cows headbutting another jogger last weekend on Meadowlark Trail. That jogger was not seriously injured, according to the outlet.