(CNN) Samuel Little, 79, confessed to strangling 93 victims between 1970 and 2005 last year -- triple the number of victims that Ted Bundy confessed to killing.

Now, the FBI is asking the public to help identify more victims of the man they say is America's most prolific serial killer

Little targeted women, often of marginalized and vulnerable groups, many who were involved in prostitution or suffering from drug addiction. Their bodies sometimes went unidentified and their deaths uninvestigated.

Samuel Little's mugshot.

The FBI is hoping to change that.

"For many years, Samuel Little believed he would not be caught because he thought no one was accounting for his victims," said ViCAP Crime Analyst Christie Palazzolo in a statement. "Even though he is already in prison, the FBI believes it is important to seek justice for each victim—to close every case possible."

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