SUMMIT COUNTY, Colo. (KDVR) — Two teenagers on a spring break vacation died Sunday after a sledding accident at a Colorado ski resort, authorities said.

The Summit County Sheriff’s Office said they responded around 8:35 p.m. for a reported sledding accident at Copper Mountain Ski Resort involving 17- and 18-year-old males from Illinois.

They reportedly rode tandem down a half pipe and launched off a large snowbank at the bottom of the half pipe. The sheriff’s office said they came down hard on the ice below, which caused blunt-force trauma.

The teens immediately received medical attention but could not be revived and were pronounced dead.

“Our thoughts and condolences go out to the families and friends of the individuals involved in this tragic incident,” Summit County Sheriff Jaime FitzSimons said.

The Summit County Sheriff’s Office said they would like to remind everyone to always practice safe snow activity habits and to be aware of the risks associated with these activities.

Under the registration for the snow play and sledding zone at Copper Mountain is a list of rules.

“Caution: Snow play can be hazardous. Risks include but are not limited to collisions with natural or man-made objects or other individuals, and variable natural and man-made walking and sliding surfaces including but not limited to snow, packed snow, and ice, and injuries or death may result,” the registration explains on Copper Mountain’s website.

Copper Mountain closes at sunset, which is around 7:12 p.m. It is unclear if the teens were in the designated area for sledding.

The Summit County Coroner’s Office is investigating the cause and manner of death of the teens. Their identities have not yet been released.