MOUNT VERNON, Wash. -- A Washington State Trooper responding to a report of a motorist brandishing a gun hit and killed a pedestrian who stepped in front of his patrol car in Mount Vernon last night. Trooper Keith Leary says two troopers were taking the southbound college way exit from I-5 just before 10 p.m. when the accident occurred. The victim has not been identified. The troopers were responding to a report of a motorist displaying a rifle to another driver on northbound I-5 near Starbird Road south of Mount Vernon. No one was injured or arrested in that incident.