(CNN) — An avalanche Tuesday near Vail, Colorado, trapped four people — killing one of them, with the other three being rescued — county authorities said.
Kris Friel, a spokeswoman for Eagle County, Colorado, initially told CNN about the fatality and added that “rescue operations” were underway targeting the three others.
The county’s sheriff’s office later issued a statement saying those three were found with non-life threatening injuries. None were transported to a hospital, instead leaving the area on their own, Vail Valley Medical Center spokeswoman Lindsay Hogan said.
The avalanche occurred near the tree line “in backcountry wilderness where they do not have avalanche control,” said Ethan Greene of the state-run Colorado Avalanche Information Center. It was not immediately clear what the four were doing at the time.
“This (avalanche) was most likely triggered by the people who got caught in it,” Greene said.
The incident occurred in the East Vail Chutes roughly 90 miles west of Denver, with authorities first being alerted around 11:30 a.m. (1:30 p.m. ET), according to the Eagle County Sheriff’s Office.
According to the Vail resort’s master development plan, “The East Vail Chutes is an extremely steep, avalanche-prone bowl that drains down to Interstate 70 or to East Vail.”
This is the second avalanche death this season in Colorado. The other happened on December 31, 2013, on Parkview Mountain, west of Willow Creek Pass.
The Colorado Avalanche Information Center noted that there have been at least five such fatalities nationwide, including a snowmobiler killed on New Year’s Day in Big Sky, Montana.
On a scale of 1 (least dangerous) to 5, the prospective avalanche rating around Vail was a 3 — the rate around which most incidents like this happen, explained Greene, especially if people get fooled by otherwise nice conditions.
“Today was apparently a beautiful day up in Vail,” Greene added, “and therefore would be an appealing day to be out in the backcountry.”
By Carma Hassan, CNN’s Greg Botelho, Ana Cabrera and Sara Weisfeldt contributed to this report.