COLUMBIA, S.C. — When Texas Rangers called Richland County Sheriff Leon Lott to let him know one of their prisoners had confessed to shooting a woman in the head 40 years ago in his county, Lott knew immediately what case they were talking about.

Back then, the sheriff was finishing his first year as an investigator. He examined 19-year-old Evelyn Weston’s body that muggy night in September 1978, noting she had been shot in the head.

Then he went to work to find her killer, a search that went on unsuccessfully for four decades.

“I’m not going to say they haunt you. But they’re always in the back of your mind,” Lott said of the violent cases he hasn’t solved in his county of 410,000 people, which he first started patrolling in 1975.

Samuel Little, 79, began confessing to crimes across the country, telling investigators he may have killed as many as 90 people, after he lost an appeal to the life sentences he is serving for strangling three women in California. All across the U.S., authorities are getting calls from a Texas Ranger who developed a rapport with Little while investigating a cold case, giving details about long-ago killings that were never released publicly, Lott said.

Weston’s death matches Little’s pattern of roaming the country, preying on drug addicts and troubled women, often near military bases, Lott said.

Little, a former boxer, would punch the victims until they were unconscious, strangle them, dump the bodies and leave town, detectives in Texas said.

Weston was found naked on a dirt road just off Interstate 20, according to newspaper accounts at the time.

Lott said he didn’t want to share any additional details about the death until investigators firm up the link between Little and Weston.