Two DSE firefighters have been killed after their vehicle was hit by a falling a tree while fighting a bushfire at Harrietville in Victoria's north-east.
The Department of Sustainability and Environment says the accident happened in the Ovens region, near Harrietville late today.
Police and ambulance officers attended the scene.
In a statement, the Australian Workers' Union says the two died heroes.
AWU Victorian secretary Cesar Melham said the loss was a shattering one for the families, friends and colleagues of those who perished.
"They have died heroes, which will be small comfort to those that grieve them," Mr Melham said.
Firefighters have been battling the blaze in the state's high country for several weeks.
The identity of the deceased is yet to be confirmed.