Dixon said he didn't immediately know whether everyone inside the house was from one family.
Firefighters reported that flames were coming from the roof by the time they arrived at the two-story house in the 6,500-person Ohio River city about 20 miles west of Evansville.
Witness Larry Schakel said he saw firefighters bring two children who appeared to be fine from the back of the house as flames shot from the structure.
"The parents were hollering there were still kids in the house," Schakel told WFIE-TV. "One firefighter went through the front area of the house, busted through the glass and started shooting water through."
The cause of the fire wasn't immediately known. The Courier & Press reported a state fire marshal's office investigator was at the scene.