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null - The "Smiley Face" murders are one of the longest-running serial killer theories in the U.S.
Since 1997, around 45 men mysteriously disappeared after a night out only to be found dead in a nearby body of water in separate incidents occurring in 11 states in 25 cities.
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In some of the cases, smiley faces were spotted by authorities near the areas where the bodies of the men were found, but police classify the incidents as "accidental drownings" but many believe there is a serial killer or gang of killers at work.
What are experts saying about the "Smiley Face" murder theory?
TMZ spoke with experts who shared their perspectives on what might have happened to these men.
Dr. Kris Mohandie, a forensic psychologist, investigated the death of Christopher Jenkins, one of the 45 men found dead. Mohandie told the entertainment outlet that Jenkins disappeared on Halloween night in 2002. Four months later, Jenkins was found dead in a river wearing his costume.
FILE-A police officer pulls police tape after a crime scene. (Photo by Aimee Dilger/SOPA Images/LightRocket via Getty Images)
Mohandie explains to TMZ that there were no signs of foul play and authorities looked into the "Smiley Face" killer theory and debunked it because of the 45 cases because the smiley faces looked different.
Ninette Toosbuy, a former Los Angeles police detective, argues that the smiley faces and bodies of the men were located in different areas, adding that the 45 men have died in the past 27 years, raising questions if these were the actions of a serial killer.
This story was reported from Washington, D.C.