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Who killed the Grinnell College coed and left her body beside a Missouri highway in 1992?


An Illinois girl bound for Iowa and found dead along a lonely stretch of a rural interstate in Missouri....


It was late August in 1992, and as is the normal scenario, thousands of young people were heading back to college from their hometowns all across the country.


Tammy Jo Zywicki, a bubbly-blonde 21-year old from Illinois, left her home in Evanston on August 23 to make the four-and-a-half hour drive to return to Grinnell College in Iowa. Between 3 and 4 p.m, Tammy seems to have experienced car trouble in central Illinois on Interstate 80 near mile marker 83 close to Lasalle, Illinois.


Eyewitnesses placed her at that location, where she was seen beside her vehicle, a 1985 Pontiac T1000. Witnesses reported seeing a tractor-trailer near Zywicki’s vehicle during this time period and a man described as a white male between 35 and 40 years of age, over six feet tall, and having dark, bushy hair.


Later that evening, an Illinois State Trooper found Zywicki’s car and ticketed it as an abandoned vehicle. The following day, Illinois State Police had the vehicle towed.

That same evening, Zywicki's mother contacted the Illinois state police to report her daughter never made it back to college and one week later, the body of the coed was found next to along Interstate 44 between Springfield and Joplin in rural Lawrence County, Missouri.


The young woman had been wrapped in a red blanket bound with duct tape, been sexually assaulted, and stabbed eight times — once in the arm and seven times in a circle around her heart.


Suspects were developed in the case, and two different truck drivers--one a confessed serial killer--was questioned in the death of Zywicki.


The official FBI report confirmed Zywicki had last been seen in the presence of a man whose appearance resembled the eyewitness’ description. One suspect was developed after she told workers of the gift of a unique watch as a gift from her truck-driver husband that closely matched the description of a timepiece Zwicki was known to wear.


The circumstantial evidence tying the truck driver--a man by the name of Lonnie Bierbolt--was pretty persuasive. Bierbodt lived close to the Missouri area where Tammy’s body was discovered and had been visiting family who lived only a few minutes from where Tammy first disappeared.


The blanket in which Zywicki’s body was found bore a Kenworth logo — the same type of truck Bierbodt drove.

Bierbodt was brought in for questioning and provided both blood and hair samples for testing before being released


Bierbodt also had a criminal record. He’d committed two armed robberies in the ’80s and officials considered him a “violent felon.” At one time he’d been serving three concurrent 20-year sentences before being released and paroled in 1990.


Lonnie Bierbodt died in June 2002 at age 41.

Confessed serial killer Bruce Mendenhall

In July 2007, FBI agents contacted investigators in Tennessee about questioning 56-year-old trucker Bruce Mendenhall in Zywicki’s slaying. Mendenhall, of Albion in southern Illinois, was arrested Thursday, July 12, 2007, and charged with killing 25-year-old Sara Hulbert at an interstate truck stop in Nashville, Tenn.


Mendenhall eventually confessed to killing six women at truck stops in Tennessee, Indiana, Alabama, and Georgia but didn’t confess to Zywicki’s death


No one has ever been arrested in the abduction and murder of Tammy Jo Zywicki.


If you have any information about Tammy Zywicki’s unsolved murder please contact your local FBI office, the nearest American Embassy or Consulate, or Special Agent Jorge Fonseca, Illinois State Police at (815) 726-6377 ext 286.




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