A 78-year-old prisoner linked himself to more than 90 murders.

Samuel Little made the stunning confession in exchange for a prison transfer after he lost an appeal, according to the FBI.

Little was apprehended at a Kentucky homeless shelter and extradited to California in 2012 for a narcotics charge. His DNA was linked to three unsolved murders during the late 1980s.

Charged with murder and convicted in 2014, he is currently serving three life sentences without the possibility of parole.

Little was able to recall details about his victims and the killings. He even drew pictures of the women he attacked, but his inability to remember dates makes it harder for investigators. He often targeted prostitutes and drug addicts. The former boxer often followed the same pattern during the killings: knock out the women, strangle them, dump the bodies and leave town. The deaths often went uninvestigated or weren't perceived as homicides by detectives. Additionally, DNA testing of evidence wasn’t available.  

Texas Ranger James Holland has interviewed Little almost daily since May to crack the cases. Holland was initially brought in by the FBI’s Violent Criminal Apprehension Program (ViCAP) to follow up on a cold case in Odessa, Texas, that matched Little’s pattern.

“Over the course of that interview in May, 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,” said ViCAP crime analyst Christina Palazzolo.

So far, Little has confessed to 90 murders across 16 states between 1970 and 2005. He maintained his innocence before the transfer deal, reports NBC News.

Little was charged with murder in Mississippi and Florida in the early 1980s, but he wasn’t indicted in the former and was acquitted for the latter. He was also imprisoned for an assault in Missouri and another assault along with false imprisonment in San Diego, California. His criminal record dates back to the 1950s when he dropped out of high school. Little got in trouble for a variety of crimes including shoplifting, fraud, drugs, solicitation and breaking and entering.

“Little is in poor health and will likely stay in prison in Texas until his death,” the FBI said in its statement.

The number of victims, if confirmed, would make Little one of the most prolific serial killers in the country’s history.

He is currently housed at Wise County Jail to be close to Holland.

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