First responders to a shooting in an east Tennessee area instead discovered a house fire with six people dead inside from an apparent murder suicide.

Another person, an adult male, was carried from the scene with a gunshot wound, according to the Tennessee Bureau of Investigation.

News Channel 9 said the incident happened in Sequatchie, an unincorporated area in Marion County about 20 miles northwest of Chattanooga.

It all developed about 9 p.m. Marion County Sheriff Bo Burnett said the incident erupted from a “domestic situation, evidently that has been ongoing for a pretty good while.”

“This is one of the worst things I’ve seen,” Burnett said. “You hear about these things but this is one of the worst I’ve been involved in all my career as a law enforcement officer.”

At least two of the victims died from smoke inhalation.

The names and ages of the victims have not yet been released, but the children’s mother and grandmother, along with the person responsible for the incident, are among the dead, authorities say.