Thousands of flying foxes died in an Australian heat wave so severe, it has melted tarmac.

The animals fell from the trees as they were boiled alive in temperatures exceeding 104 degrees Fahrenheit in Campbelltown in New South Wales.

Animal welfare volunteers battled to save the lives of the hundreds of babies and some adults in distress, but the death toll is believed to be in the thousands.

A spokesman for the charity Help Save the Wildlife and Bushlands in Campbelltown said: “The efforts of our volunteers yesterday was both heroic and heartbreaking.”

“In extremely trying conditions, they worked tirelessly to provide subcutaneous fluids to the pups that could be reached and many lives were saved. But sadly, many lives were lost too.”

“Hundreds of mainly young flying foxes were lost to the heat yesterday and the final count could run to thousands.”

The heat wave in three states brought temperatures strong enough to melt the bitumen on a highway and sparked bushfires that destroyed buildings and threatened lives.

A fire raging out of control set several structures ablaze on the outskirts of Melbourne, the country’s second-largest city and the capital of the southeastern state of Victoria, as a result of the heat wave.

The state’s emergency management commissioner, Craig Lapsley, said hot temperatures had combined with dry weather, strong winds and a wind change to create dangerous conditions.

“It’s exactly what the forecast indicated and when we have fires running, that’s obviously a problem for us,” he told a news conference.

About 400 homes lost power and 50 fires were reported across Victoria on Saturday, although many were small and were extinguished.

Emergency warnings were issued both in Victoria and in the nearby state of South Australia, where authorities advised residents of a rural area to seek shelter in buildings from an out-of-control fire.