Rescuers will resume their effort Tuesday to retrieve the bodies of five hikers who were killed after becoming trapped by a rock slide on a trail in south-central Colorado Monday.

The slide demolished a popular beginners trail below one of Colorado's most photographed mountains, causing so much destruction that rescuers had to wait a day to recover the victims' bodies.

The Monday morning slide sent 100-ton boulders onto a viewing area to see Agnes Vaille falls in Chalk Creek Canyon below Mount Princeton, a 14,197-foot peak. Five hikers were killed, and a teenage girl was left with a broken leg and other injuries. 

According to KDVR.com, the 13-year-old was airlifted to Colorado Children's Hospital in Aurora. 

Witnesses said some of the boulders were the size of cars.

A helicopter, engineers and experts from a mining company were on the scene working out a plan to reach the victims' bodies, KDVR.com reported. 

The recovery was called off Monday evening because rocks continued to shift when the coroner counted the fatalities, said Chaffee County department spokeswoman Monica Broaddus.

"The conditions are considered unstable," Broaddus said.

There was no immediate identification of the victims or whether they were a single group. A female hiker who heard the slide ran down the trail and called for help, said Chaffee County Undersheriff John Spezze.

The area had a rainy summer and a recent snowfall, said Spezze. It was too soon to know whether the weather prompted the slide, which left a football-field-sized gash in the mountainside, he said.

"It was totally unexpected. It caught everybody by surprise," Spezze said.

The trail is one of the first hikes recommended to people new to the area and is also popular with tourists, said Margaret Dean, a regular hiker who has hiked the trail with her 7-year-old grandson.

Dean, a copy assistant at The Mountain Mail newspaper in Salida, said the trail is easily accessible and provides a view of the falls and the Chalk Creek Valley in the Collegiate Peaks, which contains many mountains exceeding a height of 14,000 feet.

Agnes Vaille, the waterfall's namesake, was a Denver mountaineer who died in 1925 while attempting a difficult winter climb of Longs Peak, elevation 14,259 feet.

The U.S. Forest Service maintains the trail. Spezze said officials have asked the Forest Service for a permanent closure.

The Forest Service says the trail got medium to heavy usage. The trailhead lies across from Chalk Lake campground and is near the St. Elmo ghost town, a popular stop for tourists in Colorado's central mountains.

The Associated Press contributed to this report

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