Four people died Tuesday at an amusement park in eastern Australia as a result of what emergency officials called a "malfunction" on a river rafting ride.
The incident happened at Dreamworld in Queensland on the ride called Thunder River Rapids.
Gavin Fuller, senior operations supervisor for the Queensland Ambulance Service, told reporters two of the dead were ejected from the ride, while the other two were caught inside. He said park staffers were trying to give aid when emergency personnel arrived, but that all four people had injuries "incompatible with living."
The dead include two men and two women in their early 30s and 40s.
The ride features round rafts with six seats facing inward and safety belts that go around a rider's waist. The park's website says the rafts can travel as fast as 45 kilometers per hour through the simulated turbulent river.
Police and park officials said they are investigating what happened, and that they are not aware of any problems with the ride earlier in the day. They did not say whether there were any other passengers on the raft.
"We are deeply shocked and saddened by this, and our hearts and our thoughts go to the families involved and to their loved ones," said Dreamworld CEO Craig Davidson.
The park was closed after the incident.