Five people died when they were buried by a rock slide along a popular hiking trail in central Colorado on Monday, according to local news reports.
A 13-year-old was airlifted to a hospital earlier in the day, Chaffee County Sheriff W. Peter Palmer told KUSA-TV, but the rescue effort had been hampered by unstable rocks on the trail to Agnes Vaille Falls.
“At the time, when rescue people went into the slide, where we felt like the people were, they encountered rocks falling and more rocks sliding," Chaffee County Undersheriff John Spezze told CBS4.
Palmer speculated that recent rain and freezing temperatures may have led to a thaw-and-freeze cycle that made the rock formations along the trail more unstable.
Engineers and a local geologist had been brought to the scene to evaluate the safety of the rock slide.
“This is a very steep slide area, a very unstable rock area, and so yeah, we’re very, very concerned about that," Palmer said in an interview before the hikers' deaths were confirmed.
The Denver Post reported that officials would mount a recovery effort Tuesday morning.