Flagstaff Police are investigating a fatal crash involving a vehicle and pedestrian. Sgt Charles Hernandez says just before 1-pm Sunday, officers responded to a report of a crash in the area of South Lake Mary Road and East Frontier Avenue. He says the pedestrian, who has not been identified, was pronounced dead on scene. The driver of the vehicle remained on scene and was placed under arrest for suspicion of driving while impaired. The identities of the driver and pedestrian are pending as this is an on-going investigation.