A volunteer firefighting crew were trying to save a house from an out-of-control bushfire in catastrophic conditions when a wall of fire went over their truck.
The fire at Pomonal in western Victoria on the edge of the Grampians National Park has destroyed multiple properties and is still burning after being ignited by lightning on Tuesday.
The Country Fire Authority crew's leader Jarrod Pegg on Wednesday said the group was caught by an erratic wind change shifting the fire front, causing a burn-over event.
"There was some indication of change in weather ... and you could see the directions of the embers were starting to move," Mr Pegg told reporters at the CFA station in Wendouree.
"But then out of nowhere a significant wall of fire came over the top of us."
The volunteers took shelter under fire blankets in their tanker and made a mayday call.
"We were fortunate to have the support of another crew ... to help suppress any fire activity on our truck," Mr Pegg told reporters, and highlighted the bubbling and melted plastic on the tanker's paintwork.
The crew was treated for minor injuries at a local sportsground before returning to the fire front.
"My crew was pretty adamant and I'm pretty proud of them that they were keen to get back in the fireground as soon as we could," Mr Pegg said.
Premier Jacinta Allan also thanked the volunteers for their bravery.
"They are out there responding to the call-out, protecting the Pomonal community, and please know you have the gratitude of all of us for the selfless work that you do," the premier told reporters at the State Control Centre on Wednesday.
While the threat has eased in the Grampians National Park, two watch and act warnings for separate fires remain in place for residents to the park's north and east.
Authorities say that leaving now is the safest option for communities in Pomonal, Bellfield, Lake Fyans and Dadswells Bridge.
As many as 30 houses could be destroyed in Pomonal, but the official number of properties lost has not been confirmed.
"There are people who spent last night in a relief centre not knowing if they've got a home to go back to today, and our thoughts are with them," the premier said.
Almost all fires sparked in Victoria on Tuesday are believed to have been started by lightning strikes as severe storms lashed the state.
The State Emergency Service received more than 3800 requests for assistance since 9am on Tuesday.
The blaze near Pomonal and Bellfield, which has burned more than 2100 hectares, remains the focus of fire crews, along with another blaze near Mount Stapylton further north in the national park.
Relief centres have been set up at the Alexandra Oval Community Centre in Ararat and the Grampians Community Health in Stawell, with the Stawell hub still in operation.
The threat from an uncontrolled bushfire at Newtown near Ballarat has reduced after residents were told to evacuate from a grassfire that spread into a forest.
A fire also started at Robinvale near the NSW border and sits at an advice warning level.
Five schools and 27 early learning centres were closed on Wednesday across southwest Victoria.
Victoria sweltered through three days of hot conditions before more than 20 fires broke out on Tuesday, with emergency services reporting flame heights of up to 30 metres.
Temperatures dropped on Wednesday following a cool change but fire conditions were expected to persist.