The Ottumwa Fire Department responded to two house fires early Friday morning. At 4:40 a.m., authorities were called to the 300 block of Washington Street. The second house that caught on fire is directly behind the first. Deputy Fire Chief Cory Benge says this is the fourth or fifth time authorities have had to put out a fire at this house. No one lives in either house. Benge says the fires seem suspicious and are currently under investigation.