Twenty people were trapped and later rescued from the top of the Arkham Asylum roller coaster ride at a theme park on Australia's Gold Coast.

Four people were helped down by emergency personnel using a ladder platform, the spokeswoman said.

Australian media said that there were no reports of injuries but a triage area had been set up within the park.

General Manager of Movie World, Greg Young was quoted by local media as saying there was a mechanical problem with a chain on the ride.