After operating the vehicle normally and backing into a parking space, I stopped the vehicle and selected Park, turned the vehicle off, and exited. Before the driverâs door was closed, the vehicle began to roll forward unexpectedly. I ran back to the vehicle and reentered it to regain control, with the driverâs door still open and the seatbelt not fastened. After stopping the vehicle, I selected Reverse, at which point the vehicle surged backward unexpectedly. The open driverâs door struck another vehicle and the driver, and my vehicle continued backward, colliding with a fence and then a tree. The vehicle did not behave as expected after Park was selected, creating a serious safety risk to myself and others. Several vehicle systems appeared to malfunction or fail during the incident. The specific component or system responsible is not yet known, and the vehicle is currently available for inspection. The incident resulted in property damage and back pain, for which I later sought medical care. The vehicle has been inspected by a collision repair facility and is currently being handled through insurance. The manufacturer has been informed and stated that insurance should make determinations regarding the incident.