MADISON, Wis. -- The Madison Fire Department said that a fire at a two-story duplex Friday morning caused $75,000 in damage to the upper unit.

At 7:07 a.m. Friday, Madison firefighters were called to 270 Mayfair Ave. for a report of a fire.

When crews arrived, they did not see any visible smoke or flames from outside, but once they entered the home, smoked billowed out the door and visibility was almost zero, according to a Madison Fire Department news release.

Fire officials said crews entered the home, found the fire in a bedroom and extinguished the fire within eight minutes.

Three adults and three children were home at the time of the fire, along with a dog and three puppies. Everyone was able to escape safely.

Family reported that the smoke detector was sounding, fire officials said.

The fire also caused minimal damage to the lower unit.

The residents did not have renters insurance. The Red Cross is assisting them.

Officials said the fire is under investigation.