Tractor trailer rearends cab, kills 2 in fiery wreck

An incredible accident occurring while a was stopped at traffic lights in Mississauga at 4 a.m. Saturday. A tractor trailer slammed into the propane-fuelled vehicle with enough force to hurl it 100 metres into a ditch where it burned both the driver and passenger to death. The truck driver is practically unhurt. Question: What was he doing? Sun News story is best account.