A 43-year-old Mission man died after the truck he was driving went through a guard rail and plummeted 12 metres to the creek bed below on Sunday afternoon near Hope.RCMP Sgt. Peter Thiessen said the man, whose name has not been released, was hauling groceries in a 2010 Peterbilt semi-trailer just after 2 p.m. He had just rounded a gentle counter-clockwise curve on Highway 1 when he lost control of his vehicle.He crossed into the oncoming lane while on the Emory Creek Bridge deck, went over the curb and through the guard rail.The driver was the lone occupant of the truck, and succumbed to his injuries at the scene, Thiessen said.At the time of the accident, there was compact snow on the road with some freshly fallen snow on top, he said."At this point in the investigation, it would appear that the causal factor for this collision would be speed relative to the road conditions. However, a mechanical inspection will be conducted."Anyone who might have seen the vehicle before the collision or who witnessed the accident is asked to call Const. Roddie Cairns at the Fraser Valley Traffic Services office, 604-702-4039.