The killers behind these terrifying crimes remain unidentified to this day.
1. Redhead Murderer, or the Bible Belt Strangler
2. Zodiac Killer
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3. Alphabet Murders
4. Highway of Tears Murders
Warning sign on Highway 16.
5. Freeway Phantom
6. Long Island Serial Killer
7. Colonial Parkway Killer
8. Servant Girl Annihilator
December 1885 newspaper headline about the Servant Girl Annihilator.
9. Bible John
Composite sketch of Bible John.
10. The Cleveland Torso Murderer
Police searching for one of the Torso Murderer's victims.