Three dead after plane used in bushfire effort crashes

Police said a rescue helicopter crew spotted the wreckage and officers arrived on the scene about 5pm, confirming all three on board had died.

Queensland Fire and Emergency Services (QFES) said the aircraft had been contracted to support the bushfire response.

"It was engaged by QFES to conduct line scans, and travelling from Toowoomba to Mt Isa when it crashed near Cloncurry," a statement on Saturday night said.

"The cause of the crash is currently unknown and QFES will assist the Australian Transport Safety Bureau (ATSB) with its investigation."

The ATSB said it had started an investigation.

"A team of transport safety investigators from the ATSB's Brisbane office with experience in aircraft operations and maintenance are preparing to deploy to the accident site," a statement said.

A preliminary report is anticipated in about six to eight weeks, the ATSB said.