At approximately 1345 Eastern time, the Canada-registered airplane was substantially damaged when it impacted a wooded area. The commercial pilot received serious injuries and the private pilot-rated passenger was killed. Instrument conditions prevailed and the flight was operating under an IFR clearance. An Airmet existed for light-to-moderate icing below 14,000 feet and, at the pilots request, the aircraft was issued vectors around mountainous terrain in an attempt to remain below icing conditions. Montreal Center was issuing vectors to the aircraft when radar and radio contact was lost. The airplanes wreckage was located about one hour after the accident and the pilot was rescued. A nearby weather observation 20 minutes before the accident included winds at seven knots gusting to 14, and temperature and dew point of -7 deg. C. Moderate freezing precipitation also was reported nearby.