The Metro III passenger plane operated on a scheduled flight from Salt Lake City International Airport, UT (SLC) to Elko Airport, NV (EKO). During arrival, the flight crew of SkyWest Airlines flight 5855 requested a VOR/DME-B approach to runway 23 at the Elko Airport, which was approved. As the approach continued, the flight crew reported over the Bullion VOR. Approximately 30 seconds later, the aircraft impacted the top of a mountain, about 100 feet before reaching the VOR station. The airplane sustained substantial damage and four occupants sustained serious injuries. Elevation of the crash site was about 6460 ft. The minimum published crossing altitude at the VOR was 7000 ft. The airport was 4.1 miles from the VOR at an elevation of 5135 feet. Weather at the time of the approach was poor with low clouds. PROBABLE CAUSE: “Improper IFR procedure by the captain, and inadequate monitoring of the approach by the first officer, which resulted in a failure to maintain proper altitude during the approach. Factors related to the accident were: the terrain and weather conditions at the accident site. “