In a unique lesson on human nature, a group of Northeast Tennessee students in a high school sociology class believe they may have uncovered the faint trail of an unknown serial killer.

Teacher Alex Campbell invited his students at Elizabethton High School to re-examine a series of at least 11 decades-old, unsolved homicides across Tennessee and several other states, known as the Redhead Murders.

The result of their semester-long project, which the class is set to present at a news conference Tuesday, is the students' own detailed character profile of a single suspect they have deemed "The Bible Belt Strangler."

Using established criminal investigative techniques, the students used the Doe Network — an online national database of unidentified murder victims — news reports and other available materials to develop a list of six deaths sharing the closest similarities.

Authorities have yet to publicly establish a connection between any of the cases.

"They've never been linked together, officially," Campbell told Shane Waters, host of the Out of the Shadows podcast.

"But anybody who thinks that you have multiple killers, in the same place, with the same signature and the same (modus operandi) at the same time, is out of their mind."

A pattern of victims

All six cases, reported between 1983 and 1985, involve white female victims with red or reddish hair and slight builds, whose bodies were found close to major roadways. Several of the women appeared to have been strangled or suffocated. They are believed to have been transients who were abducted while hitchhiking or working as prostitutes. Likewise, they were people who were less likely to be reported missing.

Lisa Nichols, a 28-year-old woman from West Virginia with strawberry blonde hair, was found dead along Interstate 40 in West Memphis, Ark. in September 1984. She remains the only victim among the six who authorities have been able to identify.

The others were discovered near the areas of Littleton, W.V., Jellico, Tenn., Greeneville, Tenn., Pleasant View, Tenn. in Cheatham County and Gray, Ky.

A possible Knoxville connection

The students theorize the women may have been the victims of one man — mostly likely a commercial truck driver, who killed with his bare hands.

Given the locations of where the six bodies were found, Campbell said the killer may have lived East Tennessee.

"Knoxville is at the geographic center of the murders," Campbell said on the podcast.

Knoxville, at the crossroads of Interstates 40 and 75, also is a major transportation hub.

While the string of killings appears to have stopped, he said the Bible Belt Strangler may still be alive.

"We believe that he stopped probably because he stopped driving," Campbell told the USA TODAY NETWORK-TENNESSEE. "We believe he's still out there."

None of the victims showed signs of sexual assault or torture, leading the students to rule out lust or thrill killing as possible motives. Rather, the class concluded their suspect was a mission-oriented killer, possibly motivated by a need to remove people he perceived as undesirable or harmful to society.

Campbell said a mutual acquaintance connected him with an FBI profiler — who he declined to identify — who reviewed the students' work and validated the links they drew among the six cases.

Renewed attention

Campbell and his students hope their amateur investigation brings renewed attention to the cases.

"There's people out there who know something," he told the USA TODAY NETWORK-TENNESSEE. "We've just got to get this in front of them so they can come forward."

"I think they've learned everything in the syllabus — peers, media, racism, socioeconomics. More that they, they've learned that even when you're young you can have an impact on the world."