Four bodies were found at two separate residences in the small farming town of Laurel, Neb., on Thursday in what police are investigating as crimes, authorities said.
Local police and fire departments responded to the first residence after a witness called to report what was described as an explosion followed by fire and found one victim.
A short time later, a second fire was reported at a home several blocks away, where three more victims were found.
The incidents are being investigated as crime scenes, the Nebraska State Patrol said at a news conference.
Laurel is a small farming community located about 64 kilometres west of Sioux City, Iowa.