Logan police are investigating the possibility that the Hyrum fire, started Friday morning, may have been caused by a faulty propane tank.

Logan police chief Brad Franke said the burning debris that landed in the bed of a truck, causing a propane tank to explode, should not have affected a properly functioning propane tank.

“A propane tank should not have exploded like that,” Franke said.

The fire, which rapidly spread Friday morning to engulf five homes and a nearby field, is mostly under control at this time, Franke said. Fire crews are still working to control the one remaining home, which caught fire in the initial explosion, that is still burning out of control, Franke said.

Frank reported that the fire resulted in one fatality — the farmer whose truck exploded, seven people in critical condition and 17 others transported to the hospital with various injuries.