CHICAGO (WLS) — Officials have identified a man known as the “unknown wanderer.” They said he has a possible link to the infamous Tylenol murders in Chicago.
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Dr. Mathew Francis Betkouski was identified as the man found dead inside a Boise, Idaho church in December 1982.
He died by taking cyanide inside the church.
Police said that before he died, Betkouski received multiple treatments for mental health in the 70s.
In 1982, Betkouski was known to be doing experiments at his home, and police said he was fired after taking chemicals from his job at a lab.
He was described as paranoid, possibly having schizophrenia and a “loner.”
In 2021, his brother died, and police were able to find old items that used to belong to Betkouski, inlcuding his old desk and bed.
Police said they found homemade cyanide in his belongings; however, police said it was different than the poison used in the Chicago murders.
Maps of Chicago were also found among his things, including photos of Betkouski in the Windy City in what is believed to be December 1981.
Police said in the late 70s and early 80s he lived in California, Texas, New Mexico, Ohio and Florida. Officials are hoping to find other cold cases that involve cyanide deaths.
Idaho police said they cannot name him as a suspect in the Tylenol murders because it’s not their case.
Idaho officials sent information to Chicago and Arlington Heights; they said it’s CPD’s job to name him as a suspect.
Forensic psychiatrist Dr. Park Dietz said he worked the case in Chicago in the 80s. Dietz said when he presented the case of Betkouski to multiple forensic psychiatrists and an FBI group, they all believed Betkouski was a viable suspect.
In the fall of 1982, seven people died within 24 hours in the Chicago area after taking Tylenol that had been laced with one of the deadliest and fast-acting poisons: cyanide.
7 people died within 24 hours after taking cyanide-laced Tylenol in September 1982
The case has never been solved.
James Lewis, the only person ever convicted in connection with the Tylenol killings, died in 2023.
WATCH: I-Team Investigates: The Tylenol Murders
7 people died within 24 hours after taking cyanide-laced Tylenol in September 1982
Chicago police said in a statement, “Chicago Police Department detectives have been in contact with the Ada County Sheriff’s Office regarding its investigation to determine whether there is a connection to the Tylenol murders investigation, which remains an open cold case. Anyone with information that may assist in this investigation is asked to submit an anonymous tip through CPDTip.com or Cook County Crime Stoppers at 800-535-7867.”
Arlington Heights police said in a statement, “The Arlington Heights Police Department continues to work closely with our law enforcement partners to identify the individual or individuals responsible for the 1982 Tylenol murders. We received and reviewed information provided by the Ada County Sheriff’s Office. We remain committed to collaborating with our law enforcement partners and pursuing any viable leads as they become available. Because this remains an active investigation, we have no additional information to release at this time.”
The FBI said in a statement, “There have been repeated claims over the past 44 years about alleged links to the Tylenol Murders which have remain unsubstantiated. Out of respect for the ongoing, legitimate investigation, those impacted by the tragedy, and the law enforcement partners who have provided genuine support since the start, the FBI remains the lead on investigating and releasing credible information to the public once the evidence yields a true case resolution.”
This is a developing story; check back for updates.
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