Initial reports on Friday afternoon were that trees falling onto powerlines could have sparked the blaze which took hold just before 2pm as north-westerly winds picked up ahead of a cool change.

But weekend investigations are understood to have uncovered a number of issues which are now being investigated to determine the cause. Locals have told The Courier they understood the fire may have started along Sago Hill Road.

Ballarat CIU and the CFA are still working to pinpoint the fire's cause, and have so far been unable to rule out whether it was deliberately lit.

The Bunkers Hill fire crossed 134 hectares of land heading in a south-easterly direction towards Smythes Creek before being brought under control before the wind change pushed it towards Ballarat.

A number of houses and sheds were lost in the blaze.

Three people were taken to hospital as a result of the Bunkers Hill fire due to smoke inhalation, while three firefighters required assistance from paramedics, two for smoke inhalation and one with a 'severely lacerated hand'.

Evan Dower, who lives close to where the blaze began, in Greenhalghs Road, said in almost 20 years living in the area, he had never seen a fire like it.

"We were working in the shed and the power went out, it was only me and my eldest son Luke who were around," Mr Dower said. 

"By the time we got back to the house, it was coming down at us.

"Luke looked after the animals and rang the fire brigade and I tried to fire an arc around the house. We lost some sheds and machinery, I had to go to hospital with smoke inhalation."

Mr Dower said he initially heard that a tree had fallen onto a powerline.

"I've never felt wind like it," he said. "It was like being in a war zone, trees were falling and crashing all over the place.

"I've lived here almost 20 years and I've never had to use the fire pump before, fortunately I was able to get it going, only thing that saved the house. The firey's, police, volunteers were absolutely unbelievable, the firey's were here all night

"We lost two sheds, some quad bikes, motorbikes, splitters and lots of fences, probably about $30,000 but it could have been a lot worse."

CFA Region 15 operations manager Gavin Hope said, in all, four blazes took hold on Friday afternoon, which saw emergency warnings issued west of Learmonth and Mount Mercer while another blaze was detected at Mount Wallace.

"The Learmonth blaze we believe was a result of a previous burn off, which was of no fault of the farmer and although Geelong is handling the Mount Mercer blaze, we believe it was something similar," he said.

"We also had a small fire out at Mount Wallace, which was actually in the process in the being controlled and it jumped out of containment lines.

"The Bunkers Hill blaze is still under investigation. We had an aircraft go up on Saturday to have a look at where it burned."

Mr Hope described the cooperation of all fires crews on the day as "magnificent."

"It was a mighty effort to stop it in its tracks, it moved very quickly," he said "In all we had four incidents in the area and it did put a strain on our resources, but we managed to get enough trucks. 

"While the aircraft had been scaled back, we managed to get a helicopter just in time. The timing was impeccable. It was very sad to lose what we host, but there are a number of houses down there and without that help, it could have been much much worse.

"It was an incredible wind, it was as though a mini-tornado blew through, dangerous fire conditions are around 41km/h, we were over 100km/h."

He also singled out for praise the efforts of crews from Bacchus Marsh and Maryborough and Forest Fire Management Victoria who continued to work over the weekend, particularly in the identification of dangerous trees."

The Bureau of Meteorology said while there were no tornado's recorded in the area, winds did gust as much as 85km/h around 2pm.

And people are being warned that another similar day can be expected on Friday with temperatures expected to reach the mid 20s and winds picking up again, however the next change is not expected until Saturday morning.

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