The Civil Aviation Safety Authority has blasted the use of "unapproved" drones to capture footage of this week's bush fires as "irresponsible".
The rebuke came after a video shot from a privately-owned drone of the aftermath of the Lithgow fire in the Blue Mountains, west of Sydney, emerged earlier this week.
The footage showed the drone operating in close quarters to a water bombing helicopter. It also toured the interior of a burnt-out shed, and later soared over the heads of rural firefighters guarding the perimeter of a property from flames.
CASA's aviation safety director John McCormick called on drone owners to "use their common sense", particularly in the presence of licensed commercial aircraft.
"Flying an unapproved remotely piloted aircraft near fire fighting aircraft, fire fighters and fire fighting vehicles is dangerous," he said.
McCormick said the collision risk posed by an unauthorised drone could force firefighters to ground water bombing aircraft, "putting lives and property at risk".
The risks for pilots of water bombing aircraft were already exposed during the most recent fires. One helicopter had a near miss when the bucket it was carrying struck high-voltage wires while fighting a fire south of Newcastle, NSW.