Two homes were destroyed in a first-alarm house fire near the US 60 and Gilbert Road in Mesa Sunday afternoon.

Remarkably, nobody was seriously injured in the fire.

The Mesa Fire Department says approximately 100 firefighters responded to the blaze around 2:30 p.m. Sunday as temperatures across the Valley topped a record-setting 106 degrees for the day. The previous record was 105 degrees, set 70-years ago.

Crews from Mesa Fire and Medical, the Gilbert Fire Department and the Tempe Fire Department all assisted in containing the fire to just the two homes.

Two firefighters suffered from heat exhaustion but were not taken to the hospital. No residents were injured in the fire.

"They're producing heat by working really hard, they've got the heat coming down from the fire. That's gonna be like your oven and they got the ambient heat beating down on them so that three things can fatigue a firefighter a lot than when it's a 70-degree day," Mesa Battalion Chief Kasey Beal.

"On days when it's over 105 degrees we like to see the crews do one work cycle go to rehab while other crews work and start swapping those crews out," Beal said. "It's something they have to be mindful of and they're in their second work cycle it's gonna be more fatiguing, they need to make a consorted effort to hydrate."

Structure fires are making for some smoky skies above US 60 in the East Valley. pic.twitter.com/N6BlNRCelk — Arizona DOT (@ArizonaDOT) May 6, 2018

Firefighters are investigating what caused the fire.

RELATED: 100+ degree temperatures expected to continue into the week