MADISON, Wis. -

Four units from the Madison Fire Department were sent to put out a blaze on Madison's west side Sunday night that was caused by an outdoor sauna.

The incident happened around 7:15 p.m. in the 5600 block of Taychopera Road.

According to the Madison Fire Department, people in the neighborhood had smelled an odor for several hours, but couldn't figure out the source of the smell. About three hours later, a neighbor saw flames and smoke coming from the back yard of the home and called 911.

Smoke was so thick that it stayed at street level and covered a nearby intersection, according to the Fire Department. Four crews managed to knock out the fire within about 15 minutes.

Fire department spokeswoman Bernadette Galvez said the outbuilding housed the sauna, and office and a resting area, and suffered about $45,000 in damage. The home did not suffer any damage. No one was injured. Fire investigators determined the fire started in the sauna and was unintentional.