The CFA was called to a fire at the Prestige Mill site on Lowe Street, opposite East Grampians Health Service overnight.
A passer-by noticed flames around 2am and called emergency services.
Ballarat crews responded with their Aerial appliance along with local tankers.
The cause of the fire is still being investigated, however, it is being treated as suspicious.
The CFA said that youth enter the mill a lot and fire calls to the building are becoming more frequent.
An advice message was issued for Ararat just before 4am this morning and remains in place as of publishing.
The message warns Ararat residents that that may see or smell smoke as firefighters continue to monitor the site. Closing windows and doors can reduce smoke inside.
‘Unless the situation changes, this will be the final message for this fire,’ the warning reads.
Ararat Rural City Council will be assessing the site for safety hazards following the fire.
- Straight from our newsroom