Vehicle accelerated from a stop sign at high speed and brakes were pushed down all the way with no respond the steering wheels was stiff and the Vehicle continued at high speed on its own crashing curbs side walk vegetation along the way until final crash at a tree. not warning lamps messages and air bag did not deploy. Car engine remained on at time of crash until manually turned off. safety of driver & passenger and others near by were at very high risk. Head on collision with other vehicles and homes could have happened. Insurance adjuster inspected and determined it is a "Total Lose" but did not gave reason for incident. police report was done and suggested to follow up with dealership. Emailed about this incident to Subaru dealership. Unknown if any additional inspection was done.