Four people died on Tuesday when a ride malfunctioned at Dreamworld theme park in Queensland -- Australia's largest theme park with over 40 rides and attractions, including five roller coasters.
Two people were also trapped in the Thunder River Rapids Ride, while two others were thrown into the conveyor belt system.
"Police were called to the site at Coomera around 2.20 pm (local time) following reports that a number of people had been injured by a conveyor belt," a police statement read.
According to Gavin Fuller, acting senior operations supervisor for Queensland Ambulance Service, the victims were two males and females aged between 32 and early 40s. They sustained "injuries which were incompatible with living."
"One of the rides had sustained some sort of malfunction, causing two people to be ejected from a ride, another two people were caught inside the ride," Fuller said.
He further added that "a number" of staff from the ambulance service had been "deeply affected by this terrible incident."
The theme park's administration held a press conference after the incident took place.
"We are deeply shocked and saddened by today's accident; our hearts and thoughts go to the families involved and their loved ones," said Dreamworld's office in a tweet.
The theme park was closed "until further notice due to an incident at the park."
In a statement, Australian Prime Minister Malcolm Turnbull said that he was saddened to learn of the tragic accident. "Theme parks are a place for family fun and happiness, not tragedy. This is a very, very, sad, tragic event. Our thoughts and prayers are with the families of those who lost their lives," the PM said.
"This is a very sad day, and we trust there will be a thorough investigation into the causes of this accident over the days to follow," he added.