A toxicology report on a heli-ski guide involved in a fatal avalanche March 13 found marijuana-based THC in his blood at higher than background levels.

Alaska Heliskiing guide Robert Liberman, 35, and client Nickolay Dodov, 26, were killed in the avalanche that occurred during a commercial trip by Alaska Heliskiing. Four other clients were in the group during the morning outing on a peak near the Tsirku River. Recent autopsies of the men showed both…