Dramatic footage of a fiery motorway crash in Canada has been captured on amateur video.A truck is seen hurtling down the wrong side of the motorway in Edmonton, into the path of oncoming traffic.The vehicle eventually plunges over the guard rail of an overpass and onto railroad tracks below, exploding into a large fireball and killing the 25-year-old driver, Mark Santos.Although dozens of terrified motorists were forced to swerve or drive into the ditch on Monday to avoid a collision, none were injured.Mr Santos's family is refuting witness accounts that the truck may have purposely swerved towards vehicles before it crashed.Jordan Santos said his brother was a diabetic who sometimes had trouble remembering what he did when his blood sugar levels were low.Edmonton Police Services said they were trying to "determine if there were any psychological conditions".