BOULDER COUNTY, Colo. — Numerous agencies responded to Eldorado Canyon State Park about 1:45 p.m. Friday after the man was reported pinned under a boulder weighing approximately 2,000 lbs.

Search and rescue teams were contacted by a witness who took them to the man.

The Boulder County Sheriff’s Office says a man was hiking with two other people when they went off the trail and into some open space.

“They went off trail into a scree field. And while they were walking around that, he was walking around a larger rock, and when he put his hand on it, the rock shifted, pinning his foot and leg,” says Richard Peebles with the sheriff’s office.

Peebles was one of more than a dozen first responders on scene working to free the man before sunset.

Rocky Mountain Rescue Group, a volunteer-based organization, assisted in the rescue. Its members are specially trained to deal with rescues like this one.

RMRG’s Drew Hildner says the steep slopes and unsteady boulder field made for a difficult rescue.

“It’s almost like solving a complex math problem,” says Hildner. “You have to make sure if you’re moving one thing, you’re not going to shift everything else as well.”

Hildner says they used air bags, pulleys and lifts to free the man. The entire process took roughly four hours.

“We were able to roll the boulder just enough to free the patient’s foot and leg,” says Hildner. “It requires thinking outside the box, using multiple different solutions.”

The sheriff’s office and RMRG were assisted with personnel from Rocky Mountain Fire, City of Boulder Open Space and Mountain Parks, City of Boulder Fire, City of Lafayette Fire and North Metro Fire.

“Between using all the tricks in our tool bag, [firefighters] using their tricks from vehicle extraction and us using some of our mountain rescue skills, we worked together as a team to free the patient,” he says.

The man was taken to a local hospital with serious injuries but is expected to survive. His identity has not been released.