Two firefighters were killed and three others were injured while battling wildfires in Australia, according to the New South Wales Rural Fire Service. Geoffrey Keaton, 32, and Andrew O’Dwyer, 36, were in a truck fighting fires southwest of Sydney when a tree fell and caused the vehicle to roll off the road, the Rural Fire Service said. Three other firefighters were taken to the hospital for severe burns, the Associated Press reports. The three firefighters are in stable condition, said New South Wales Premier Gladys Berejiklian. Prime Minister Scott Morrison, who has been criticized for taking a vacation while the fires raged, said he would return to Sydney immediately following the firefighters’ deaths. “They were bravely defending their communities with an unmatched spirit and a dedication that will forever set them apart amongst our most courageous Australians,” he said in a statement. Australia has been facing unprecedented heat in addition to the wildfires—the country reached its hottest temperature ever two days in a row this week, with the country-wide average temperature reaching 107.4 degrees Fahrenheit Wednesday.