FOND DU LAC (WLUK) -- An early morning house fire at a single family home needed more than just the Fond du Lac Fire Department to put it out.
At 4:56 a.m., authorities were called to investigate an area for a source of smoke. As their search continued, a 911 call reported that the smoke was coming from 386 Ledgeview Avenue.
When crews arrived, they found extensive smoke and fire coming from the residence.
A mutual aid box alarm was called, which sent off-duty Fond du Lac authorities along with several neighboring fire departments to the home to help extinguish the flames and investigate the cause of the fire.
Authorities believe the fire started in the basement. No one was home at the time of the fire.
Fire crews had to fight the fire from outside the house after part of the first floor collapsed, making it too unsafe for crews to work from the inside. Authorities say the fire caused extensive damage to the inside of the house.
The department shared video on Facebook and photos on Twitter.
No other details are available at this time.