Rescue workers Friday afternoon were responding to an avalanche that buried a person near Ophir Pass, northwest of Silverton.
Authorities heard about the slide about 2:45 p.m., said Keri Metzler, coroner for San Juan County.
Two helicopters were ferrying rescue workers into the area Friday evening, she said. One was approaching from the Telluride side; the other was approaching from Silverton.
Officials were uncertain if the victim was in San Juan or San Miguel county.
The victim was wearing an avalanche beacon, she said.
Rescue workers reached the person about 5:45 p.m. and were performing CPR. It was unknown if the person was going to survive, she said.
Further details were not immediately available Friday night.