Fifteen vehicles destroyed as fire rips through Perth mechanic workshop

A suspicious fire has ripped through a Perth mechanic business, destroying more than a dozen cars parked for repairs.

The arson squad is investigating whether a firebug cut their way in before setting the workshop alight. 

Fifteen vehicles fed the flames as five fire trucks rushed to Speedline Auto Repair on Colin Jamieson Drive in Welshpool about 5.45am today.

"[Fire crews] made access through the front gate, and basically threw a stream of water between the cars and the building to stop it spreading into the structure," Perth fire station district officer Ben Borrett said.

The building was barely damaged but 14 cars, including a Volvo and BMW parked to be repaired, were incinerated.

A refrigerated truck from a storage facility on site was also destroyed.

The business owners, who 9News understands were not insured, were distraught today.

"Yeah I think they're a bit shaken up," Borrett said.

"Not the best phone call to receive at 6am in the morning."

The cause of the fire has not yet been determined but the arson squad is investigating  after finding a large hole cut into the business' fence. 

The cars are now trapped in a crime scene, their owners waiting to see whether they're covered for the damage.

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