The contact owns a 2011 Mazda CX-9. The contact stated that while attempting to park the vehicle at a slow speed in the driveway, the vehicle suddenly experienced unintended acceleration, lurched forward, and crashed into a tree before coming to a stop. The contact was unable to stop the vehicle during the sudden unintended acceleration. During the failure the vehicle sustained front end damages, but no air bags had deployed. No injuries were reported. The cause of the failure was not yet determined. The contact stated that twice in the day before the unintended acceleration, the vehicle jerked forward in traffic however, the contact attributed the issue to the brake pedal not being firmly depressed or the clutch not properly engaged while shifting gear. The local dealer was notified of the failure, but no assistance was offered. The manufacturer was not yet contacted. The failure mileage was 173,000.