Firefighters were called after a resident observed a fire in bracken about halfway up the mountain near Hogarths Road West just before 5pm.

The resident tried to extinguish the flames as they called 000.

Both the Country Fire Authority and Forest Fire Management Victoria responded to the incident.

The fire moved up the north side of the mountain but due to difficult terrain, firefighters were forced to wait for the fire to burn up to where they were positioned before they could contain it.

Dozens of firefighters worked to contain the fire amid warm weather and thick smoke on the ground, while a helicopter assisted from the air.

In all, 17 vehicles were at the scene including 12 tankers, three ultralight tankers and district cars, in addition to the Helitack 368.

The fire was declared under control about 7.40pm - almost three hours after it started. It was extinguished about 8.30pm, with crews leaving the scene about 9pm.

It is estimated that the fire burnt through about 10 to 15 hectares of land.

Related coverage: Firefighters win battle against fire at Mt Buninyong

The fire did not pose a threat to private property or life, though an Advice warning was issued to residents living in the area.

The cause of the blaze is yet to be determined but it is believed it could be suspicious, with police saying a person was spotted leaving the scene as the fire took hold.

Ballarat Criminal Investigation Unit detectives are investigating.

CFA commander Stephen Poulter said while the rain on Wednesday had been beneficial, there were still smouldering stumps in the fire area.

Crews are continuing to monitor the area, while the City of Ballarat is calling in arborists to check trees for any safety concerns.

Road closures remain in place around the mountain, which could be closed for a few days.

Commander Poulter reminded people preparing their properties for the upcoming fire season to check the weather conditions for the day of the burn and the days afterwards beforehand.

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He reminded people not to leave the burn-off unattended, and to ensure they have water and equipment on hand to douse the fire if it gets out of control.

The district's firefighters have been called out to respond to burn-offs unnecessarily in recent weeks, so Commander Poulter encouraged people to register their burn-offs to prevent this from happening.

To register your burn-off, call 1800 668 511.