FAYETTEVILLE, Tenn. — Authorities sought to assure the public that a serial killer was not on the loose when they revealed Friday that two suspects in a string of murders on the Tennessee-Alabama state line have been in custody for months.

Lincoln County Sheriff Murray Blackwelder said the suspects, who were not named, have been in custody since October on unrelated charges. They remain in the Madison County jail in Alabama.

“Within 48 hours, we had two people in custody who we believe to be involved,” he said.

Blackwelder said the suspects have not yet been charged in connection to the deaths of three women, a toddler and two men who were found in four locations in Lincoln County and over the state line in north Alabama in October. Blackwelder did not want to name the suspects because he did not want to jeopardize the case.

Authorities have said the killings were not random, and Blackwelder said there was no threat to the public. “There is not a serial killer running loose,” he said.

On Oct. 22, investigators found the bodies of Chabreya Campbell, 22, her 18-month-old son and her friend, Amber McCaulley, 21, at a home near Fayetteville in Lincoln County.

Hours later, the body of Jessica Brown, 21, was found in another home in the same county. A 3-year-old-boy and an infant survived the slayings, officials said. Campbell also was pregnant.

Police wanted to question Warren Vincent Crutcher, 24, but they said he also was the victim of a homicide when his body was found dumped in north Alabama woods just across the state line the next day. Another man, Jeffrey Pope, was found dead in a Huntsville home, killed by a gunshot wound. Police have said Crutcher knew or had relationships with all the victims.

District Attorney Robert Carter said they are waiting on evidence analysis from the state crime lab, including DNA, weapons, ballistics and other evidence gathered at the four crime scenes.

Carter said they have asked the Tennessee Bureau of Investigation to expedite the analysis, but he had no time table on when charges could be filed.

Authorities have not released many details about the killings, including how the victims were killed or why.