DEVELOPING: One or more shooters are believed to be on the loose, "armed and dangerous," after a brutal string of shootings in four homes killed a total of eight family members in southern Ohio Friday, investigators said.

The eight relatives -- seven adults and a 16-year-old boy -- were apparently shot in the head "execution-style," Ohio Attorney General Mike DeWine told reporters.

At least three young children survived. One was 4 days old, one was 6 months old, and the third was 3 years old, Pike County Sheriff Charles Reader said. The youngest baby was found in bed next to the child's dead mother.

DeWine said the family's last name was Rhoden, but did not give first names. "If I was a member of that family, I would be extra cautious right now," the attorney general added.

Reader later told a late night news conference he had spoken with the family and gave them "precautionary measures to take."

Asked if he had a message for the killer or killers, Reader replied, "we're coming."

Investigators said it was possible more than one shooter attacked the family because the homes were spread out roughly a mile and a half apart. Three of the four homes were on the same street in Piketon. 

One relative discovered the horrifying scenes as she came to the homes to feed dogs and chickens, part of her morning routine, a family member told the Cincinnati Enquirer.

Ohio Gov. John Kasich called the reports "tragic beyond comprehension."

The attorney general said a motive was unclear, and that investigators would remain at the homes "for some time," likely into Saturday morning.

The family members who died had attended nearby Union Hill Church for years, according to Pastor Phil Fulton. "They kind of dropped by the wayside probably three, four years ago, maybe... The kids seemed friendly, always you know, just good kids, seemed like," the pastor told WKRC.

Ohio's Bureau of Criminal Investigation sent more than a dozen agents to the scene, officials told Fox 28.

The FBI in Cincinnati confirmed it offered help to the Pike County Sheriff's Office. Adams County Ohio Valley Schools briefly went on lockdown, Fox 19 in Cincinnati adds.

The bureau sent crime scene investigators, special investigators, criminal intelligence agents and cyber crime investigators. 

Police closed off roads around the homes as paramedics rushed to the area. Piketon is in the Appalachian region of Ohio, roughly 75 miles east of Cincinnati and 70 miles south of Columbus.

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