Major Sydney road reopens after gym fire

One of Sydney's major roads has reopened in both directions after a suspicious fire at a gym on Parramatta Road caused traffic chaos.

The blaze at Auburn has been brought under control with firefighters stopping it from spreading to neighbouring buildings on Tuesday morning.

The fire in the two-storey building is being treated as suspicious and a crime scene has been established, said Superintendent Greg Rankin.

Firefighters have still not been able to enter the site because of stability issues caused by heavy gym equipment and roof solar panels.

No injuries have been reported.

Parramatta Road reopened in both directions at around 8.30am.