Huge Melbourne factory fire started by car driven into building and set alight

Police are today investigating a suspicious factory fire in north-west Melbourne which started when a car was driven into the building.

More than 80 firefighters were called to the factory at Barrie Road in Tullamarine about 3am to find the two-storey building, about 350 square metres in size, engulfed in flames.

It was later brought under control and extinguished.

LIVE UPDATES: Tropical Cyclone Alfred nears Queensland coast

Police say the fire began when a car was driven into the building and set alight, causing major damage.

No one was inside at the time.

Firefighters extinguished the fire early this morning.

Nearby gas outlets and power lines were also made safe as part of the operation.

Residents are being warned of significant smoke within 2km of the scene.

Motorists are urged to avoid the area as it is anticipated to have major impacts on local traffic in coming hours.

Police say a crime scene is in place and an arson chemist will attend later this morning.

Anyone who witnessed the incident, has dashcam/CCTV footage or information is urged to call Crime Stoppers on 1800 333 000.