Aviablog

Australian police officers were checking traffic speeds with a radar gun on a nearly-deserted road, somewhere in the outback.
They spotted a vehicle appearing from behind a hill on the horizon and aimed their gun at it, only to see the speed indication shoot up to over 800 km/h (500 mph), after which the machine packed up. For a brief moment they figured the machine was faulty.
A split second later, a very low-flying F/A-18 roared over their heads, making the officers duck to the ground and kicking up dust all around them.

The chief of police sent in a complaint to the local air force base about the "irresponsible behaviour of the jet's pilot."

The base commander replied with a letter, thanking the police for their efforts with helping to investigate the "incident."
The letter went on saying that the F/A-18's computer systems had picked up the radar gun's signals and identified them as a possible threat to the aircraft, jamming the signal from the radar gun - the machine was not faulty, as the police officers had thought. The computer had then started to configure the fully-armed aircraft for an attack, locking one of its air-to-ground missiles onto the radar device. The pilot "fortunately" identified the situation and performed a manual override of the jet's system to prevent the missile from being launched to destroy the "hostile radar device."

I wonder if those cops will ever use a radar gun again