Six taxis destroyed by fire at Tullamarine

A fire that destroyed six taxis and a damaged a factory near Melbourne's Tullamarine Airport is being treated as suspicious.

No-one was injured in the fire which broke out about 12.30am on Wednesday when neighbours noticed one cab ablaze in Derby Street.

The fire spread to the other five cars, destroying all six cabs and damaging the factory facade, before being brought under control.

The fire is being treated as suspicious and a crime scene remains at the site as police continue their investigations.