CANBERRA: Initial investigations, according to Queensland Police, indicate that the crash occurred as one aircraft was taking off and the other was landing.
The same chopper carried those who passed away. The conditions of three additional passengers are critical.
Minor injuries were sustained by five out of the six passengers aboard the other aircraft, which had to make an emergency landing.
The crash, which occurred at around fourteen in the morning local time, is being looked into by the Australian Transport Safety Bureau (ATSB) (04:00 GMT).
About 75 kilometers (47 miles) south of Brisbane, the two planes came down close to the Main Beach tourist area.
According to Queensland Police Service spokesperson Gary Worrell, the same aircraft was involved in all four fatalities and three critical injuries.
He described the situation as challenging. It was challenging to obtain access to the spot and dispatch our emergency personnel in time to handle the situation effectively because of where it was positioned, on a sand bank.
Images from the accident site show the area littered with wreckage and a broken helicopter that appears to be resting upside down next to the Seaworld resort.
The other helicopter, which is marked on its fuselage with the emblem of a well-known marine park, appears to have made an emergency landing following the incident.
Sources claim that in addition to conducting other charter activities, the park provides tourists with sightseeing helicopter flights.
Local police have blocked off traffic on Seaworld Drive, the main entrance to the marine park.
They advised drivers and pedestrians to stay away from the area while emergency personnel assessed the situation.
Investigators from the ATSB's Brisbane and Canberra offices have been dispatched to the location to gather information, examine the wreckage, and speak with witnesses.
Eyewitnesses who witnessed the crash or the helicopters in flight have also been urged to get in touch with the ATSB's head commissioner, Angus Mitchell.
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