The FBI this week released additional information on the professed serial killer Sam Little, the jailed Texas man who has confessed to 90 murders between 1970 and 2005. The majority of those confessions have not yet been matched to victims, including three that describe murders in Arkansas.

From an FBI news release this week:

A 78-year-old man sitting in prison in Texas may be among the most prolific serial killers in U.S. history, FBI crime analysts report. According to the Texas Rangers, Samuel Little has confessed to 90 murders to date, and the FBI is working with the Department of Justice’s Bureau of Justice Assistance, the Texas Rangers, and dozens of state and local agencies to match Little’s confessions with evidence from women who turned up dead in states from California to Florida between 1970 and 2005.

Little was arrested in a homeless shelter in Kentucky in 2012 and extradited to California on a narcotics charge. Once in custody, a DNA match to Little was discovered on three unsolved homicides involving women being beaten and strangled. He was convicted on three counts of murder and sentenced in 2014 to three life sentences, without parole.

Little had previously been arrested for murder at least twice in the 1980s but was not convicted. Authorities suspected that there were more victims. Eventually, Little began making confessions last spring to a Texas Ranger who suspected him of a murder in Odessa, Texas.

Here’s FBI crime analyst Christina Palazzolo’s description:

He went through city and state and gave Ranger Holland the number of people he killed in each place. Jackson, Mississippi—one; Cincinnati, Ohio—one; Phoenix, Arizona—three; Las Vegas, Nevada—one.

Little confessed to 90 murders, and federal authorities began working to match up evidence of murders to the confessions. Thus far, they have confirmed 34 killings, “with many more pending confirmation,” according to the FBI.

Federal authorities continue to investigate Little’s confessions that remain uncorroborated. In almost every case, his targets were prostitutes and drug addicts — murders that were more likely to receive little or no investigation at the time. In some cases, the bodies were never identified and remain “Jane Does.”

While Little remembers the details of the victims and the murders in great detail, including drawing pictures of many of the women, he is fuzzy on the timeline, creating challenges for investigators trying to look back decades to corroborate the confessions.

Federal authorities have not yet released a list of the corroborated killings, but the FBI this week released information, including an interactive map, revealing the locations and estimated dates of “unmatched” confessions that have not yet been definitively corroborated by authorities, as well locations and dates for victims who have not yet been identified (Jane Does).

Three of Little’s still-unmatched confessions involve women in Arkansas:

North Little Rock, Arkansas
Unmatched Confession: Black female killed in 1992 or 1993.

Pine Bluff, Arkansas
Unmatched Confession: Black female killed between 1990 and 1997.

West Memphis, Arkansas
Unmatched Confession: Black female between 28-29 years old killed in 1984. Victim picked up in Memphis, Tennessee.

More from the FBI on Little’s M.O.:

Little chose to kill marginalized and vulnerable women who were often involved in prostitution and addicted to drugs. Their bodies sometimes went unidentified and their deaths uninvestigated.

Little’s method of killing also didn’t always leave obvious signs that the death was a homicide. The one-time competitive boxer usually stunned or knocked out his victims with powerful punches and then strangled them. With no stab marks or bullet wounds, many of these deaths were not classified as homicides but attributed to drug overdoses, accidents, or natural causes.

L.A. Times reporter James Queally wrote an excellent deep-dive report on the Little Case. From his story:

Property records also show Little lived in Florida and Louisiana for several years, but investigators mostly described him as a transient who tended to float in and out of cities throughout the Southeast. Court records show he has been arrested at least 30 times on minor offenses, including shoplifting, petty theft and battery, in Ohio, Florida and Mississippi.

Often, investigators said, Little would stay in either halfway houses or hostels, eschewing a permanent address as he moved from city to city.

Each place he went, they said, a similar pattern would emerge: Little would pick up a prostitute — often a black or Latino woman — and she would wind up fighting for her life. Rarely would the woman win.

All of his known victims died by strangulation, investigators said.