A firefighter working to control a blaze was mocked by a group of men who snatched his keys and threw them into the bushes.
The captain of the Sutton volunteer brigade approached the group on Saturday evening after he saw them doing "burnouts" near the spot where a fire started on Wednesday.
"The local station were out there mopping up the fire near Sutton," Southern Tablelands Superintendent Peter Alley said.
"The captain noticed a big cloud of smoke out near towards the original fire."
The group of about 14 were warned by the captain that pieces of burnt rubber could fly into the surrounding parched fields and ignite.
"He went down there in his fire vehicle and saw some hoons doing burnouts," Superintendent Alley said.
"He confronted them about it because he was worried about a piece of burnt rubber landing in the field and causing a fire."
One of the men reportedly took the keys from the station ute the captain was driving and tossed them into the bushes.
Another allegedly tried to intimidate him as he confronted the group by driving towards him at speed.
"They took the keys out of his vehicle and threw them into the paddock," said Superintendent Alley.
"Certainly they moved a vehicle in his direction."
Amateur footage obtained by Fairfax Media showed one of the cars skidding down the road before a group of volunteers showed up in aid of the fire captain.
Superintendent Alley said it was hugely disappointing to see volunteers treated with such little respect and said he would be pursuing the incident further.
The incident occurred around 6pm on Saturday near the intersection of Mulligans Flat and Read Road.
The fire at Mulligans Flat started last Wednesday afternoon about eight kilometres north-west of the village of Sutton.
It burnt through more than 500 hectares in a matter of hours before it was brought under control on Thursday morning.
The Sutton fire followed a blaze in nearby Tarago that destroyed more than 3300 hectares.
NSW Rural Fire Service spokesman Greg Allen said residents across the region should remain vigilant and follow the directions of firefighters if they found themselves in danger.
