An eyewitness to the rollercoaster crash at Alton Towers has told ITV News he was ignored when he tried to warn staff about an empty carriage on the track.
Four people were seriously injured when a car carrying 16 passengers crashed into another empty one on Tuesday afternoon.
The man, who wished to remain anonymous, said he saw empty test carriages being sent round the Smiler ride, while his children were in the queue.
He noticed that one car had become stuck halfway round, and approached a member of park staff with concerns.
Minutes later, he watched with horror as the car carrying passengers was released and sent round the track.
"I was going ballistic. I was going mad. I was watching and it and knew there was nothing I could do about it. As soon as it started, you knew what was going to happen."
Alton Towers remains closed for a second day as an investigation into the crash continues.
A spokesperson for the park said: "At present we are working closely with the Health and Safety Executive to investigate the incident. We cannot comment further on individual speculation."