NBC News

Four people who were found shot to death in a car in northwest Alabama had been implicated in a Tennessee child pornography investigation and may have ended up killing one another in a murder-suicide plot, authorities said Thursday.

The car and its grisly contents were discovered Wednesday night by the side of a logging road in William B. Bankhead National Forest near Double Springs, about 65 miles northwest of Birmingham.

Authorities wouldn't release the identities of the victims — three white men and a white woman, all from Tennessee, ranging in age from their mid-20s to early 50s. Three of the victims were related.

But Winston County Sheriff Rick Harris told NBC station WVTM of Birmingham that two of them had been scheduled to appear in court Wednesday in Tennessee on child pornography charges. The two others had been implicated in the same case but not charged, he said.

Harris told The Cullman Times that investigators were exploring the possibility of a murder-suicide.

"Whatever started in Tennessee seems to have ended in Winston County," he said. "We absolutely do not believe there is anyone dangerous still running around in our county."

"Our question is why they wound up in our state," Harris told the newspaper. "We're sure their problems originated elsewhere. I don't think in any way our county is in danger. Nobody should fear who is next."

Harris said more information might be available Monday once forensics testing is completed.

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