PALMER, Alaska — A helicopter crashed in the area of Knik Glacier killing five and leaving one in serious but stable condition, Alaska authorities said.

Alaska State Troopers said in a statement Sunday that they received a report of an overdue helicopter and the location of possible crash debris Saturday night.

A rescue team from Alaska Rescue Coordination Center was dispatched to the crash site just after 10 p.m., troopers wrote. The team arrived to find five occupants dead and a sole survivor, who was taken to a hospital.

No identities were immediately released, but authorities are notifying next of kin.

The Alaska State Troopers, Alaska Army National Guard, and Alaska Mountain Rescue Group will attempt recovery efforts at the site Sunday.

The National Transportation Safety Board will be investigating.