SILVERTON, Colo. (AP) — All four people aboard a small plane were killed when it crashed in the southwest Colorado mountains, authorities said Sunday.

The single-engine plane was flying from Durango to Aspen when it crashed Saturday afternoon. Local officials say the crash site was about 1½ miles north of Silverton.

None of the victims’ names have been released, and the cause of the crash was unknown. The National Transportation Safety Board will investigate.

The Socata TB-21 left Durango at about 1:30 p.m. Saturday. About 40 minutes later its emergency beacon signal was detected near Silverton, The Denver Post reported.

Bad weather cut short the search on Saturday. Temperatures in Silverton dipped to 4 degrees between Saturday night and Sunday morning, and 8 to 10 inches of snow had fa

llen at the scene after the crash, San Juan County Emergency Manager Kristina Maxfield said.

The plane crashed in a rugged, heavily forested area up to 11,000 feet above sea level, Maxfield told The Associated Press.

Maxfield said a search team reached the crash site Sunday and found two bodies, which were being carried to waiting vehicles, and an autopsy was planned for Monday. She and Federal Aviation Administration spokesman Mike Fergus both confirmed to the AP that there were no survivors.