Sketches by a serial killer in prison: A possible Las Vegas victim pictured

In 2018, Samuel Little confessed to murdering 90 people over the span of 35 years, launching law enforcement investigations across the country.

Little says one of those murders happened in Las Vegas, but investigators haven't been able to corroborate that claim as of yet.

The FBI provided News 3 with this statement:

The FBIs Behavioral Analysis Unit (BAU) provided behaviorally-based assistance and case linkage analysis for the Samuel Little case through the use of their Violent Criminal Apprehension Program (ViCAP) national database. Little has confessed to 90 murders to date, and the FBI’s Violent Criminal Apprehension Program is working with partners nationwide to match those confessions to killings that occurred between 1970 and 2005. Thus far, 36 cases have been corroborated through investigative activity as attributable to Little.

Earlier this week, the FBI released sixteen sketches drawn by Little, as they attempt to identify more of his victims.

Among the sixteen sketches is that of the woman he says he killed in Las Vegas in 1993.

“The portrait, while it is a good piece of evidence, you have to connect it to something. It may well be that this victim, if indeed there was a victim, was never discovered," retired homicide detective Phil Ramos said. “I think you’ve got to look at the credibility of this suspect. Many times we’ve had serial killers come forward and give false confessions.”

The FBI put out the sketches in the hopes to identify more of Little's victims, in order to, "provide closure and justice in unsolved cases."

However, identifying those victims may prove to be challenging for many reasons, including the time period and his methods of killing, according to Ramos and the FBI.

“It’s really hard, really hard to get something started without somebody coming forward, other than this alleged killer, saying, ‘I know who that girl was,'" Ramos said. “I don’t think there is any way to prove that he actually killed 90 people, because it’s been going on for so long, according to him.”

Investigators say Little often targeted women who were vulnerable and at risk, often addicted to drugs, or worked as sex workers.

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.

Little is currently serving three life sentences in a Texas prison for three murders he says he did not commit.

He was sentenced in 2014 after DNA evidence linked him to victims in three, unsolved Los Angeles cold cases from the 1980s.

The FBI's Violent Criminal Apprehension Program (ViCAP) put together a background on Little and found there appeared to be a pattern in his killings, according to the FBI.

“Serial killers are a very rare breed. They’re hard to track down until they get caught, or until one of their victims escapes," Ramos said. “If in fact that’s true. If he did kill 90 people, law enforcement would be very lucky to be able to solve and identify 50% of those.”

Local law enforcement are leading the investigative efforts to confirm the information Little has provided, according to the FBI.

If you recognize anyone from the sketches, you're urged to contact the ViCAP tip line at 1-800-634-4097, or by emailing vicap@fbi.gov. They also say people can call their local law enforcement agency or FBI Field Office.