Monday afternoon, investigators say a woman was seriously injured at Keystone when a snowboarder hit her before fleeing the scene.

"We have skier collisions that happen all the time, that happen in the four different resorts that never rise to the level of a criminal act," Sheriff Jaime FitzSimons, Summit County Sheriff, said. "This was clearly a violation of the Skier Safety Act."

FitzSimons says slopeside hit-and-runs happen about a half dozen times each year between Keystone, Breckenridge, Copper Mountain, and Arapahoe Basin. The sheriff says people should remain at the scene and offer aid in the event of a collision.

"We have a responsibility to our fellow human, I mean, to leave someone in that condition on the mountain," FitzSimons said. "It's just more about we shouldn't do that to people. We should be a lot kinder."

Unfortunately, Mary Chambers says the same kind of thing just happened to her son, Christian, on Wednesday.

"A guy came zooming down and I would've hit him, so I turned and I ran into the tree," Christian said.

Mary Chambers says another male snowboarder hit her son forcing him to crash into the forest.

"He was coming out of the trees and a person just went and kinda clipped him," Mary Chambers said. "He had to have hit him a decent amount hard for him to hit a tree."

Christian now has a big bump over his right eye and an injured wrist.

"All I saw was his clothing because he went in front of me," Christian said. "He had a gray helmet and a red jacket."

Sheriff FitzSimons says people should remember details like that to help investigators.

"We do ask that people look for any identifying marks that stand out is really the easy one. whether it be a type of jacket, color of jacket, helmet, goggles," FitzSimons said.

The 52-year-old woman hit on Monday is a worker at Keystone who was off-duty, according to a statement from Keystone Resort:

"On Tuesday, Jan. 3 Keystone Resort Ski Patrol responded to a hit-and-run collision that occurred on the mountain involving a 52 year-old female skier, and an unidentified male snowboarder.

Keystone Ski Patrol attended to the victim and she was transported to the Steadman Clinic in Vail, Colo. for further care and evaluation. Ski Patrol requested a description of the other party involved to alert resort staff and assist in the search. The resort is cooperating with the Summit County Sheriff’s Office to assist in finding the snowboarder involved in this incident. The victim was an off-duty Keystone employee.

Keystone Resort places the highest value on safety. If guests are involved in a collision resulting in injury, Colorado law requires that all parties remain at the scene of the incident. Guests should immediately call Ski Patrol to attend to the scene and facilitate the exchange of information between the parties involved. Guests who are involved in a hit-and-run incident should contact Ski Patrol immediately to report the incident and provide a detailed description of the skier or snowboarder involved."

The sheriff's department issued this description, "The snowboarder was described as 5’9”, 160 pounds, wearing a black and red Ruroc Inferno full-face helmet and light brown pants."

If you have any information on the case, please call Detective Scott Wagner at 970-423-8913.

The sheriff says his detectives usually catch the culprits who leave the scene.

"We catch them pretty often because everything is tracked on the mountain," FitzSimons said. "You're making it worse if you run."