The collapse of the ice tunnel caused a large amount of debris to fall on one snowboarder.
The other six snowboarders were able to escape and were not hurt.
Rescue crews attempted to determine how safe the scene was before preparing a plan of action, according to the Hood River County Sheriff’s Office.
The collapse happened around 4 p.m. near the White River Glacier and Palmer Glacier area of Mount Hood.
Originally, officials thought an avalanche had occurred, but they later determined it was an ice cave that collapsed.