Adelaide mattress fire contained

A fire at a mattress recycling factory in Adelaide's south has been contained.

About 60 firefighters from the Metropolitan Fire Service (MFS) attended the Hackham facility at 5.30am on Wednesday.

Crews brought in a bulldozer to demolish parts of the structure and say no other neighbouring properties are at risk.

The blaze is causing smoke to drift over a wide area, prompting a warning for residents to stay inside if possible and drivers to use caution.

Police say the cause of the fire is not yet known.