Authorities are investigating a suspicious house fire in Evansville.
Central Dispatch sent firefighters to 714 E. Iowa St. just after 5:00 Monday morning.
In a release, Division Chief Mike Larson said crews found a two-story house with flames coming from the first-floor windows.
Firefighters extinguished the blaze in about a half-hour.
They were sent back to the scene about three hours later to douse hot spots.
Larson said the house was vacant and unsecured, with evidence of homeless activity on the second floor.
He said the fire originated in the front living room which created a large hole that burned through the floor and exposed the basement.
Firefighters initially attacked the fire from the exterior due to the danger of falling into the basement.
The fire department contacted Evansville Police for an arson report, but Larson said the extent of the damage with no witnesses will likely keep the cause of the blaze undetermined.
No one was injured.