The most severely injured, Chris Klinga, 25, was in intensive care and listed in serious condition Monday night, according to a spokeswoman at St. Anthony's Central Hospital.

Klinga's climbing partner, Chris Lee, 37, said his friend sustained two broken legs after a large rock fell from above.

"Chris was in the line of fire," Lee said from his hospital room in Boulder.

Both men were climbing a route known as Doud-Griffith, off of the Redgarden Wall.

Lee said he was leading the climb and grabbed hold of a large rock that came loose. Klinga was on-belay about 50 feet below, Lee said.

"(The rock) hit me when I came to a halt, because Chris caught me," Lee said. "Then it kept going and hit Chris."

Lee estimated the rock to be about three feet long, two feet wide, and 6 inches thick. Lee said he was relieved the rock missed hitting either of them on the head.

"It could've been worse," Lee said.

Climbers in the area called 911 and volunteers from Rocky Mountain Rescue Group performed the technical rescue.

"This evacuation was more challenging than most, simply because of the area where they were injured," said Jeff Sparhawk, public information officer for the team.

Sparhawk said the Rocky Mountain Fire Authority assisted, as did rescuers from Evergreen, Aspen and Vail who happened to be training in the area.

Both victims had all the proper equipment, were very experienced climbers, and familiar with the route they were on, officials told 7NEWS.

Lee said the rock that came loose had chalk on it, a sign many other climbers have hoisted themselves on it countless times before.

Weather may have dislodged it, according to Sparhawk. When snow melts, it can cause loosen rocks on hillsides.