WHILE TRAVELING 50MPH WITH THE CRUISE CONTROL ON, WENT TO APPLY BRAKES TO RELEASE CRUISE CONTROL & FAILED TO RELEASE OR TO SLOW DOWN VEHICLE. INSTEAD, VEHICLE STARTED TO INCREASE IN SPEED & HIT A CONCRETE BARRIER. ALSO HAD HIT OR CLIPPED 2 OTHER VHEICLES. THEN THE VEHICLE SLID SIDEWAYS & CAME TO A STOP. NO INJURIES. *AK