CNN —
Two British nationals, believed to be a married couple, were among the four people killed when two helicopters collided in mid-air near Australia’s Gold Coast on Monday, police said on Tuesday.
Investigators believe one helicopter took off while the other landed, authorities said Monday. One crashed on a sandbar near shore, photos showed the plane upside down while the other helicopter landed safely.
All dead and seriously injured were in the crashed helicopter. Six people in the other helicopter were only slightly injured.
The pilot and three passengers, ages 36 to 65, died at the scene, according to Queensland State Police.
A 10-year-old boy was critically injured and remains in critical condition. Also seriously injured were a 9-year-old boy, now in stable condition, and a 33-year-old woman in critical but stable condition, police said.
The collision happened near the popular tourist strip of Main Beach on the Gold Coast, opposite Sea World Resort.
A helicopter was a few hundred meters airborne, although the exact height of the collision has yet to be determined, Australian Transport Safety Bureau (ATSB) chief commissioner Angus Mitchell said on Tuesday.
“We’re still determining the exact sequence of events, but from the footage we’ve seen and the damage we’re observing, it appears that the main rotor blade of the helicopter taking off collided with the forward cockpit of the descending helicopter on the left side,” he said. “We still have to determine whether that was the very first point of impact.”
The helicopter taking off had been airborne less than 20 seconds before the collision – and hit the ground within seconds, he added.
Mitchell said investigators were working to salvage the wreckage and would be interviewing witnesses and survivors over the next few days.
The investigation will look at a range of influences, including the weather, how long the helicopters were in operation, how long the pilots had flown and what was happening in the cabins, Mitchell said.
In a message on its website, Sea World Helicopters said it was “devastated by the tragic accident.”
“Our deepest sympathy and condolences go out to everyone involved at this very sad time. We are closed until further notice and will refund all tickets purchased,” the statement said.
Village Roadshow Theme Parks (VRTP), a division of Village Roadshow Limited which operates theme parks and attractions in Australia and the United States, offered its condolences in a statement on Gold Coast Sea World’s Facebook account.
It added that it is working with emergency services and supporting its team members. “As this is now a police investigation, we are unable to provide any further information at this time,” the statement said.
Australian Prime Minister Anthony Albanese tweeted his “deepest condolences” to those affected. “Australia is shocked by the news of the terrible and tragic helicopter accident in the Gold Coast today,” he said on Monday.