SYDNEY, Australia -- Wildfires raged across southern Australia on Friday, killing one man and destroying several homes as sweltering temperatures brought fresh misery for firefighters battling dozens of blazes amid a relentless heat wave.

The man's body was discovered in a burned-out car near the small town of Seaton, about 200 kilometres east of Melbourne in Victoria state, police said.

The man, who has not been identified, was the first person killed in the hundreds of wildfires that have been raging across the continent since the Australian summer began. A 61-year-old firefighter was found dead on Sunday a few kilometres (miles) from a back-burning operation in the island state of Tasmania. Officials have not yet determined how he died.

Wildfires are common throughout Australia in the summer, although record-high temperatures and dry conditions in many areas have added to the ferocity of some blazes.

Several exhausted firefighters in the country's most populous state of New South Wales collapsed from the heat on Friday, with temperatures soaring past 40 degrees Celsius in many areas. Sydney hit a record 45.8 Celsius, beating the previous high of 45.3 C set in 1939. The city's withering heat was temporary, though, quickly plummeting into the 30s within an hour.

Some relief was in sight, with cooler temperatures and rain predicted across much of the country's southeast for the weekend. Still, many of the fires were expected to continue burning for weeks.

"It's a very dangerous environment we're experiencing today," Victoria Country Fire Authority operations manager Bill Johnstone said. "Given the conditions, it's probably as bad as it can get."

Four holiday homes and one residential house were destroyed near Seaton in a fire that rapidly swelled to 45,000 hectares on Friday. Fire officials lowered the alert level for the blaze Friday night and were working to contain it.

"We're certainly here for a very protracted fire fight," Johnstone said. "We could be here for days, possibly weeks."

Two houses were destroyed in a fire in southern New South Wales' Bega Valley, the state Rural Fire Service said. More than 100 fires were blazing across New South Wales, though only two fires were threatening homes.