KANSAS CITY, Kansas (KCTV) – Investigators said they discovered a gas leak in the Excelsior Springs home that exploded early Friday morning.

The Clay County Sheriff’s Office said 70-year-old Oliver W. Campbell and 65-year-old Katherine A. Campbell both lived in the home. They also found the remains of a dog in the rubble.

The house exploded at 4:45 a.m. on Friday morning. The explosion was felt for miles around the small community in Missouri.

“Due to the force of the explosion and the extent of the damage to the building, neither the cause of the gas leak nor the source of ignition could be determined. The Missouri Division of Fire Safety classified the explosion as unexplained,” the sheriff’s office said in a statement.

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According to the Missouri State Fire Marshal, it could take up to 30 days for the entire investigation to be completed.

The sheriff’s office said there was no evidence of foul play.

Neighbors said they did not know the couple well, but they would relax on the porch every morning with their small dog named Cinnamon and wave to them as they passed by. They also said Oliver Campbell worked for many years at a container company. Both victims were retired, according to several neighbors.

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