Police are investigating after it was claimed a motorist released an ambulance's handbrake as a heart attack patient was being treated inside it.
Eric Whiteway is now recovering from his heart attack (Pic: Daily Post)
The car driver was allegedly annoyed he could not get out of a carpark at a doctor's surgery and so tried to push the ambulance out of the way himself.
North Wales Police confirmed they are investigating the road rage incident in Kinmel Bay near Abergele, Conwy.
Patient Eric Whiteway, 77, who is now recovering, said: "It's unbelievable."
He had collapsed with a heart attack at his doctor's surgery and staff had called the ambulance.
But it is understood while Mr Whiteway was receiving treatment in the back of the emergency vehicle, the motorist asked paramedics to move it.
When he was told they were busy treating a patient, it is alleged he jumped into the front cab and released the handbrake himself.
"The next thing the ambulance was moving across the car park," Mr Whiteway told the Daily Post newspaper.
"The ambulance lady said: 'My God, we're moving. She jumped out. The ambulance lady pulled him out by the scruff of his neck."
"You can't rush an ambulance. You need a bit of patience and a bit of tolerance. He wasn't very sympathetic."
Ambulance union representative Jason Williams appealed for people to let paramedics carry out their jobs.
"Our ambulance crews are working hard to help the community's emergency medical needs, especially at this busy time of the year," he said.
"Interference in their work may stop the crews from applying the necessary treatment to a patient as quickly as possible to help give them the best chance of survival."
A spokesman for the Welsh Ambulance Services NHS Trust said: "It is inappropriate for the trust to comment further on this particular incident as the matter is in the hands of the police."