Four men and one woman have perished in a fiery plane crash at Caboolture, north of Brisbane.
A male pilot, two skydiving instructors and two skydiving customers died when the Cessna 206 plummeted to the ground shortly after taking off at 11.30am on Saturday and burst into flames.
Family members witnessed the devastating scenes unfold from the ground, Moreton police region Superintendent Michael Brady said.
"It's a tragedy for all people involved, particularly loved ones and family and of course people on scene," he said.
Firefighters rushed to the scene of the blaze but could salvage little as flames engulfed the recreational aircraft.
Witnesses at the airstrip who immediately rushed to the scene were also powerless to help.
Superintendent Brady said the plane crashed at the end of the runway during takeoff and it was unclear what height it fell from.
"The impact of the crash meant it was unsurvivable," he said.
The police officer said investigations were continuing into the cause, with both QPS forensic investigators and the Air Traffic Safety Bureau combing the remnants of the plane for clues.
"It will be going on throughout today and tomorrow," he said.
"The airport will remain closed for all of today and some of tomorrow, if not all of tomorrow."
Investigators would also speak to witnesses as part of the probe, he said.
"There were a number of witnesses on the airfield at the time," he said.
He said it was unclear if family members had witnessed the actual point of impact and it was not known if the skydiving customers were members of the same family.
Superintendent Brady said preliminary investigations gave no clue as to what caused the crash.
"We don't know what happened," he said.
"It crashed at the end of the runway during takeoff."
Counselling would be offered to all emergency services who attended the scene, he said.
Earlier, airport safety officer Bryan Carpenter of Aerodynamic Flight Academy Caboolture told Sky News that the Cessna 206 lurched sharply to its left at an altitude of 100 to 200 feet.
The craft then struck a crossing runway before bursting into flames.
The presence of high-octane fuel meant the fire took over quickly.
Mr Carpenter said the incident was the worst accident recorded in his time at Caboolture Airport, 50km north of Brisbane.
He identified the crash site as on the north-eastern perimeter of the airport, away from busy Bruce Highway.
A Queensland Fire and Emergency Services spokeswoman said it took fire crews 10 minutes to douse the flames from the crash.
Mark Thompson from the Caboolture Warplane Museum was among the first on the scene.
‘‘It was hard getting close. You can’t put that type of fire out with hand-held extinguishers,’’ said Mr Thompson, who ran about 200 metres after hearing a loud thud and seeing a plume of smoke.
Both Mr Carpenter and Mr Thompson said it was the worst crash they’d seen at the airport.
‘‘They’ve had a couple of incidents here but nothing like this,’’ said Mr Thompson.
Mr Carpenter, who has worked at Caboolture for 14 years, said the crash could have been caused by any number of things.
‘‘One of the things one would expect would be an engine failure but the engine was delivering power on touch down,’’ he told Fairfax Radio Network.
‘‘So it’s something mechanical I would say ... or the pilot could have blacked out - any number of scenarios; it’s a bit like MH370 at the moment, we just don’t know.’’
- with AAP