Rescue workers struggled over the weekend to reach the twin-engine Piper PA-31 Navajo because of poor visibility at the remote, high-altitude site about 225 kilometres where it crashed on Saturday.
It's not clear what led to the accident involving the plane, whose registry matches one belonging to Regina, Saskatchewan-based Oracle Geoscience International, which provides aerial survey services to the mining industry.
Col. Carlos Silva, director of the Air Force command and control center, said the plane was seen from the air upside down on the ground.