One person died and another was hurt when their helicopter crashed on Thursday onto a frozen reservoir in southeast Idaho, authorities said. First responders travelled to the site using snowmobiles and found two people inside the helicopter, it said. 

One was dead, and the other was taken to a hospital for treatment and expected to survive. Deputies secured the area and notified the Federal Aviation Association and National Transportation Safety Board, the sheriff’s office said. Officers also located a downed power line in the area, but the cause of the crash was under investigation.