Mr Hughes flew a drone above the blaze, behind Mushy’s Tyre Service in Horsham, after fire crews requested his help.

“We were checking if there was any heat coming from the side of the building,’’ he said.

MORE PICS, VIDEOS: Fire burns behind Mushy’s Tyre Service in Horsham

Mr Hughes said the drone also helped crews see where water was running.

He said it was the first time he had helped the fire brigades.

Country Fire Authority District 17 operations officer Alfred Mason said fire investigators were working to find out the cause of the fire.

He commended the fire crews for their work.

"The volunteers fire-fighters did a really good job to contain it to what it was," he said.

He said a pile of about 500 car bodies was lost in the blaze, worth about $400,000.

"The potential of the fire was probably greater," he said.

"If they hadn't contained it to the one stack – you're talking millions of dollars."

Mr Mason said the fire was brought under control about 7.30pm, with most emergency crews sent home about midnight.

He said a small number of firefighters stayed on until 6am to monitor the site.

Mr Mason said Horsham crews were supported with resources and crews from Ararat, Ballarat, Dimboola, Dooen, Green Lake, Jung, Laharum, Murtoa, Natimuk, Vectis, Warracknabeal and  Wonwondah.

He said Horsham Rural City Council provided a water tanker, Horsham State Emergency Services provided lighting and Victoria Police helped with traffic diversions.