2016 LEXUS NX Vehicle Speed Control Problems

Upon entering a parking lot yesterday and heading down a small ramp my 2016 Lexus NX 200 spontaneously accelerated and even with my foot on the brake did not stop. I was unable to control my car and ending up hitting a tree. All of the airbags deployed; the windshield cracked; the body of the car was severely damaged and I suffered injuries. The car was brought to a body shop and is available for inspection. Fortunately, no other cars were in the parking lot and no one else was hurt. The car will be inspected over the next few days. There weren't any warning signs. I cannot say for sure what mechanical failure occurred to cause the accident, but there was clearly a mechanical failure as the acceleration was beyond my control.