UPDATE, Monday, 9.20am:
Police have repeated a request for information after a 40-hectare grass fire near the Warrnambool airport at Mailors Flat mid last week.
Detective Senior Constable Wayne Ryan, of the Warrnambool police crime investigation unit, said a police arson chemist had been unable to determine the cause of the blaze.
"We want to speak to anyone who was driving past that location and saw anything suspicious, such as a vehicle parked on the side of the road, or anyone who has dash camera footage," he said.
"It's believed the fire started between 11.45am and noon on Wednesday last week, Australia Day, on the Koroit-Mailors Flat Road.
"The cause of the fire has not been determined.
"The arson chemist found there was a lot of debris on the side of the road, but little glass or brake pads which could be an indicator of the cause.
"If anyone saw anything in that area, sparks coming off a vehicle, or anything like that, we want to hear from them.
"The cause of the fire could be accidental, we simply don't know at this stage. It's being treated as a single incident," he said.
Anyone with information is requested to contact the Warrnambool police CIU on 5560 1153 or Crime Stoppers on 1800 333 000.
Wednesday, January 26:
About 100 acres of grassland is believed to have been burnt by fire at Mailors Flat.
Warrnambool police Acting Senior Sergeant Jason Dance said the fire started on the side of the Koroit-Mailors Flat Road about 12pm.
"Hot and windy conditions have caused the fire to spread quickly and that has continued to burn through about 100 acres of grassland," he said.
"No property has been damaged, livestock has not been lost and there are no injuries."
Acting Senior Sergeant Dance said the cause of the ignition was unknown.
"CFA and aerial bombers have done a terrific job in containing the fire, which is now under control," he said.
Police are calling for any witness that were in the area at the time of the fire or anyone with dash cam footage to contact the Warrnambool station or Crime Stoppers.
Earlier, 12.55pm: The CFA has advised the fire is now under control.
Earlier, 12.30pm: A grassfire is burning through paddocks near the Mailors Flat airport.
Water aircraft is helping to extinguish the blaze, a Country Fire Authority spokesman said.
The aircraft is drawing water from the airport and can carry 3000 litres of water at a time.
He said the fire, on the Mailors Flat-Koroit Road, started before noon on Wednesday.
"It started opposite the airport," the spokesman said.
"It is running through paddocks. Ten CFA brigades have been requested and for aircraft to assist."
The cause of the fire is currently unknown but investigators have been called.
The CFA is diverting traffic from the Mailors Flat-Koroit Road on to Sims Road.
Conns Lane and Tower Hill Road is both closed to traffic with police diverting traffic at those intersections.
An advice warning has been issued for Dennington, Mailors Flat, Warrnambool, Woodford and Yangery.
There is currently no threat to residents, but people should stay informed and monitor conditions.
What you should do:
Impacts in your area:
This message was issued by Country Fire Authority.
The next update is expected by 26/01/2022 02:30 pm or as the situation changes.
Use multiple sources to stay informed:
The following services can help you, or someone you know, access information during an emergency.
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