TEXAS -- Convicted murder and former boxer Samuel Little has confessed to killing 90 people since the 1970s.[br /][br /]If the number of killings Little claims to have committed proves true, it would make him one of the most prolific killers in U.S. history.[/url][br /][Ads /][br /]Ted Bundy confessed to 30 homicides from about 1974 to 1978. John Wayne Gacy killed at least 33 boys and young men in the 1970s.[br /][br /]Little, 78, is serving a life sentence for murdering three women in California.[br /][br /]Now, officials around the country are working to investigate his claims.[br /][br /]So far, the Federal Bureau of Investigation said it has corroborated 36 of the killings, [url HREF="https://abcnews.go.com/US/fbi-unraveling-true-extent-convicted-killers-crimes-confesses/story?id=59466648" TARGET="new" REL=""][b]ABC News reported[/b][/url].[br /][br /]Now, they're working to confirm another 60 in 16 states across the country, which span more than 40 years.[br /][Ads /][br /]In many cases, Little claims he strangled his victims--who were often vulnerable women involved in drugs or prostitution--in the back seat of his car, ABC News reported.[br /][br /]The cases were often not investigated or occurred before DNA profiling existed.[br /][br /]Little evaded police for years, but it wasn't until he was picked up for a drug charge in 2012 that officials started to connect the dots.[br /][br /]Authorities said DNA evidence linked him to three unsolved murders in the late 1980s.[br /][br /]"In all three cases, the women had been beaten and then strangled, their bodies dumped in an alley, a dumpster, and a garage," the FBI said a report.[br /][br /]He was extradited to Texas in July and charged with the 1994 murder of an Odessa woman.[br /][br /]One of Little's confessions involves the fatal shooting of a woman in Richland County, South Carolina, in September 1978, the Associated Press reported.[br /][Ads /][br /]Records state that Little confessed to shooting Evelyn Weston, 19, in the head.[br /][br /]Another killing is of an unidentified 19-year-old woman in Laurel, Maryland, more than 45 years ago.[br /][br /]According to the Associated Press, Little said he picked the victim up at a Washington bus station and she indicated she was recently divorced, from the Massachusetts area and might be a mother.[br /][br /]Detectives are working to identify her.