The most significant incident involving limb loss at Alton Towers occurred on June 2, 2015, during the "Smiler" rollercoaster crash. Two young women, Leah Washington and Vicky Balch, each lost a leg as a result of the collision between a moving carriage and a stationary one on the track. Leah Washington, who was 17 at the time, had her left leg amputated above the knee, while Vicky Balch, then 20, underwent an amputation of her right leg below the knee after multiple surgeries failed to save it. In total, five people were seriously injured in the crash, and several others sustained minor injuries. The incident led to a massive investigation by the Health and Safety Executive, resulting in a £5 million fine for the park's operator, Merlin Entertainments. Since then, the park has implemented much more rigorous safety protocols and automated override systems to prevent similar accidents, but the "Smiler" crash remains one of the most high-profile safety failures in the history of the UK leisure industry.