(Portland, OR)  --  Portland police are still investigating a crash that killed one pedestrian and injured another on the Burnside Bridge.  Authorities say 36-year-old George Ben Carlson of Northeast Portland died after being hit by a vehicle that drove up onto a sidewalk on the bridge Sunday afternoon.  Thirty-five-year-old Bridget Larrabee suffered serious injuries that aren't considered life-threatening.  The driver, 59-year-old Douglas Walker of Beaverton, cooperated with the police investigation.