LOUISVILLE, Ky. (WDRB) -- An accident at an Australian theme park left four people dead.

It happened Tuesday while two men and two women were on a river rapids ride at Dreamworld in Queensland.

Officials say two people were thrown from the ride when their raft was going up a conveyor belt and flipped. The other two were trapped underwater or caught up in machinery.

The victims are in their 30s or 40s.

Investigators are still trying to figure out why the ride malfunctioned.

"That was probably the first ride we went on this morning," Craig Sneddon said. "We thought being quite a tame ride that our kids will be fine with it. So, yeah, couldn't imagine anything like this happening. So sad."

The park closed following the accident.
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