Crime Solvers Central
Crime Solvers Central
302 Cases Solved. Advancing justice for missing persons, unsolved homicides, unidentified and unclaimed remains.

Case Description

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Summary based on the NamUs case record (MP40045) and 5 other sources
In the spring of 2003, a sense of quiet concern began to ripple through a community in Illinois with the disappearance of Mark Zimmerman. At 41 years old, he was last seen in Round Lake, a village in Lake County, on the first of May. The circumstances surrounding his disappearance were, and remain, largely unknown, leaving a painful void for those who knew him. Details about his life and the specific events leading up to the day he went missing are not widely available, adding to the mysterious nature of his case. He was a Caucasian male with blond or strawberry blond hair and hazel eyes. His height was estimated to be between 5 feet 10 inches and 6 feet 2 inches, and he weighed approximately 165 to 170 pounds.

The investigation into Mark's disappearance was handled by the Round Lake Police Department. Despite their efforts, the case yielded few clues, and the trail eventually went cold, classifying it as a cold case. Information regarding what he was wearing at the time he was last seen or whether he had any personal belongings with him has not been made public. Similarly, there is no available information about his mode of transportation or his intended destination on that day. The lack of concrete details has made it incredibly difficult for both law enforcement and his family to piece together the puzzle of his last known movements.

Years have passed since Mark Zimmerman was last seen, and his case remains an open and unresolved missing person investigation. His disappearance is a source of ongoing pain and uncertainty for his loved ones. The official records, including the National Missing and Unidentified Persons System still list him as missing, with the circumstances of his disappearance noted as 'unknown'. The case serves as a somber reminder of the many individuals who vanish without a trace, leaving behind a legacy of unanswered questions and a hope that one day, answers will come to light. The Round Lake Police Department continues to hold the case file, awaiting any new information that might finally shed light on what happened to Mark Zimmerman.

Last Seen: May 1, 2003

Possible Unidentified Matches (10)

Unidentified remains cases whose details are consistent with this person, ranked by how closely they compare. Fields that are unknown in either case are left out of the score.

83%Moderate
John Doe — Chicago, Illinois
UP139126 • Found Jun 8, 2006
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Sex ✓Male
Age 100%Est. 38–52 vs 41 when missing
Race 100%White
Location 94%34 mi away, same state
TimingFound 3 years after last seen
Height 100%6'1" vs 5'10"–6'2"
Weight 100%150 lb vs 165–170 lb
Eyes 60%Brown vs Hazel
82%Moderate
John Doe — Chicago, Illinois
UP8357 • Found Oct 8, 2006
View case
Sex ✓Male
Age 100%Est. 40–55 vs 41 when missing
Race 100%White
Location 93%34 mi away, same state
TimingFound 3 years after last seen
Height 100%5'10" vs 5'10"–6'2"
Weight 100%160 lb vs 165–170 lb
Hair 50%Brown vs Blond
Eyes 60%Brown vs Hazel
80%Moderate
John Doe — Chicago, Illinois - unidentified case UP11512
John Doe — Chicago, Illinois
UP11512 • Found May 2, 2013
View case
Sex ✓Male
Age 100%Est. 45–60 vs 41 when missing
Race 100%White
Location 92%41 mi away, same state
TimingFound 10 years after last seen
Height 100%5'11" vs 5'10"–6'2"
Weight 100%149 lb vs 165–170 lb
Hair 50%Brown vs Blond
79%Possible
John Doe — Chicago, Illinois - unidentified case UP53660
John Doe — Chicago, Illinois
UP53660 • Found Oct 22, 2018
View case
Sex ✓Male
Age 100%Est. 28–42 vs 41 when missing
Race 100%White
Location 92%41 mi away, same state
TimingFound 15 years after last seen
Height 100%5'10" vs 5'10"–6'2"
Weight 81%203 lb vs 165–170 lb
Hair 50%Brown vs Blond
Eyes 60%Brown vs Hazel
78%Possible
John Doe — Illinois - unidentified case UP17083
John Doe — Illinois
UP17083 • Found Sep 1, 2017
View case
Sex ✓Male
Age 100%Est. 28–42 vs 41 when missing
Race 100%White
Location 90%47 mi away, same state
TimingFound 14 years after last seen
Height 100%5'9" vs 5'10"–6'2"
Weight 70%123 lb vs 165–170 lb
78%Possible
John Doe — Chicago, Illinois - unidentified case UP6966
John Doe — Chicago, Illinois
UP6966 • Found Apr 15, 2010
View case
Sex ✓Male
Age 85%Est. 38–55 vs 41 when missing
Race 100%White
Location 92%41 mi away, same state
TimingFound 7 years after last seen
Height 100%5'10" vs 5'10"–6'2"
Weight 100%180 lb vs 165–170 lb
77%Possible
John Doe — Chicago, Illinois
UP13750 • Found Mar 9, 2015
View case
Sex ✓Male
Age 85%Est. 45–65 vs 41 when missing
Race 100%White
Location 92%41 mi away, same state
TimingFound 12 years after last seen
Height 100%6'1" vs 5'10"–6'2"
Weight 63%216 lb vs 165–170 lb
Hair 70%Gray vs Blond
Eyes 60%Brown vs Hazel
77%Possible
John Doe — Chicago, Illinois
UP129259 • Found Nov 26, 2003
View case
Sex ✓Male
Age 85%Est. 23–45 vs 41
Race 100%White
Location 93%34 mi away, same state
TimingFound 7 months after last seen
Height 75%5'3"–5'10" vs 5'10"–6'2"
77%Possible
John Doe — Illinois - unidentified case UP10829
John Doe — Illinois
UP10829 • Found Sep 14, 2011
View case
Sex ✓Male
Age 96%Est. 50–60 vs 41 when missing
Race 100%White
Location 90%47 mi away, same state
TimingFound 8 years after last seen
Height 100%6'3" vs 5'10"–6'2"
Weight 0%259 lb vs 165–170 lb
Hair 50%Brown vs Blond
Eyes 100%Hazel vs Hazel
77%Possible
John Doe — Waukegan, Illinois - unidentified case UP163526
John Doe — Waukegan, Illinois
UP163526 • Found Apr 8, 2026
View case
Sex ✓Male
Age 100%Est. 50–65 vs 41 when missing
Race 100%White
Location 99%13 mi away, same county
TimingFound 23 years after last seen
Height 68%5'7" vs 5'10"–6'2"
Weight 100%151 lb vs 165–170 lb
Hair 70%Gray vs Blond
Eyes 30%Blue vs Hazel

These comparisons are generated automatically from public NamUs case data and are not confirmed identifications. Only DNA, dental or fingerprint comparison by investigators can confirm an identity. If you believe two cases are connected, contact the agency handling the unidentified case.

Unidentified photos are blurred because many are post-mortem. Tap a photo to reveal it.