A crane has toppled onto a factory in Melbourne's south-east, causing extensive damage to the building and forcing the evacuation of employees.

No-one was injured when the crane came down about noon on Monday at a plastics manufacturer on the Frankston-Dandenong Road in Dandenong.

A crane has fallen onto a factory in Dandenong Credit:9News

The Country Fire Authority sent four units to the Martogg Group factory and brought the situation under control in about half an hour.

Wild wind and rain lashed areas of Melbourne on Monday but it's not known if weather was a factor. Worksafe crews are now investigating.