A bushfire that was threatening properties south of Ballarat in central Victoria has been contained, the Country Fire Authority (CFA) said.

Key points: The blaze was threatening homes near a plantation on Ballarat's southern edge

The blaze was threatening homes near a plantation on Ballarat's southern edge The CFA said one shed had been destroyed

The CFA said one shed had been destroyed Firefighters expect to be on the scene for days

An emergency warning was issued at 12:20pm for the suburbs of Mount Clear and Sebastopol. The warning was downgraded to a watch and act message about 3:20pm.

Marianne Lawson told ABC Statewide Drive police knocked on the door of her 85-year-old mother and brother, who has an acquired brain injury and is prone to seizures when anxious, about midday and told them to walk to a nearby shopping centre.

Residents in homes along Whitehorse Road have been urged to leave. ( ABC News: Bridget Rollason )

"They were unable to do that because they've got limited capacity to do that, and they were just left," Ms Lawson said.

"I think it's horrendous."

Ms Lawson said she got a call from her mother, but was not allowed into the area to collect the pair.

They were later dropped at a road block by a neighbour who had chosen to remain to defend their house.

The ABC has contacted Victoria Police for a response.

Police urged residents near the pine plantation to leave their homes as soon as possible. ( ABC News: Bridget Rollason )

An aged care facility in Sebastopol was also evacuated, but residents have since returned.

The blaze destroyed one structure and several vehicles, and blackened 19 hectares.

CFA incident controller Anthony Pearce said the fire had threatened homes on Tinworth Avenue in Mount Clear, but all residents were told it was safe to return to their homes at a community meeting this evening.

The cause of the fire is under investigation.

Firefighters say the bushfire has engulfed at least one structure. ( ABC News: Bridget Rollason )

Mr Pearce said it appeared the fire started in a pine plantation.

"The fire took hold very quickly," he told ABC Radio Ballarat.

"It was what we call crowning, burning into the tree tops, within a matter of minutes of us being called.

He said firefighters would remain at the scene for "a number of days".

The bushfire was moving towards Whitehorse Road in Mount Clear. ( ABC News: Bridget Rollason )

Mount Clear resident Rowena Morgan said she came outside her house this morning to discover "dense black smoke with a glow to it".

"It was very intense and very frightening and I got in touch with my kids to get them home and rescued whatever we had in the house, what they valued," she said.

"You just don't think that you're ever going to be involved in a fire or a fire alert."

Rowena Morgan said she and her children were preparing to leave their home. ( ABC News: Bridget Rollason )

Ms Morgan said a home was destroyed when a similar bushfire broke out in the nearby plantation about 10 years ago.

Mild conditions are expected overnight, but with strong winds forecast for tomorrow, a firefighting helicopter is being kept in the area.