An 18-year-old has died after being flung from a rollercoaster called Inferno (Catalan for Hell) at the Terra Mitica theme park in Benidorm.
It is believed the teenager fell from the ride after his harness failed.
The teen was on holiday with his parents and a friend when the accident occurred.
It had originally been reported that he was British, but a local police spokesman has now said the boy was from Iceland.
A British mother at the scene told of her horror.
Lynn Alexander, from Glasgow, on holiday in Benidorm with friends and her family, said her daughter had been on the ride just five minutes before the incident.
Speaking to the Mirror, she said: "It's totally shocking. We actually had our back to the ride as we had just picked the girls up and were walking away but then we heard these loud gasps.
"The park got everyone off the ride but it seemed to take ages. Then we saw the teenager's family and they were obviously distraught.
"What surprised me is that they didn't even close the park down. We are still in shock and can't believe it. My daughter is so shaken up as she could have been in the same seat just five minutes earlier."
According to the Metro, the boy received multiples fractures and head wounds, and died after suffering a heart attack in the ambulance.
The Independent reports that a court in Benidorm has launched an investigation. A source told the paper: "The judge is awaiting a police report after which he will decide what action to take."
The Inferno rollercoaster was unveiled to the public in 2007, and is located in the Egyptian-themed area of the 14-year-old park.