Case of slain Grinnell student remains unsolved after more than 30 years
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Who is Tammy Jo Zywicki?
She was the victim in a murder-abduction mystery with Iowa ties that has gone unsolved for more than 30 years, despite an investigator's expression of strong suspicions about a now-dead trucker.
A native of New Jersey who grew up in South Carolina, Zywicki, 21, vanished in central Illinois on Aug. 23, 1992, after her car broke down on Interstate 80 as she was driving to Grinnell College to begin her senior year.
The 21-year-old's disappearance after dropping her brother off at Northwestern University in Evanston made international news.
Her petite body was found nine days later, about 500 miles away in a ditch off a stretch of Interstate 44 between Springfield and Joplin in Missouri. She had been stabbed eight times, raped and rolled up in a red blanket, sealed on both ends with duct tape.
The case — featured on CNN, the "Oprah Winfrey Show" and "America's Most Wanted" — triggered thousands of leads, including suspicion that convicted murderer and suspected highway serial killer Bruce Mendenhall could have been to blame.
But Illinois State Police investigator Marty McCarthy, who retired in 2001, said several times there was compelling circumstantial evidence that Lonnie Bierbrodt, an ex-con trucker with ties to both Illinois and Missouri, should be the prime suspect.
Bierbrodt died in 2002 and Zywicki's family still has no answers. McCarthy told the Des Moines Register in 2014 the Illinois state police and FBI appeared to give up on Bierbrodt as a suspect after the 20th anniversary of Zywicki's death in 2012.
McCarthy said Hiram Grau, Illinois State Police director from 2011 to 2015, showed an interest in the case and contacted him. But after Bierbrodt's ex-wife refused to talk to investigators ― who a nurse at a health clinic reported had showed off a musical watch similar to one that belonged to Zywicki and went missing after her abduction ― the trail appeared to run out.
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According to McCarthy, Bierbrodt lived in Missouri, close to the stretch of highway where Zywicki's body was discovered. He drove a Kenworth truck, according to news reports, and the red blanket in which Zywicki's body was found had a Kenworth logo.
Bierbrodt, a LaSalle County native, confirmed to investigators that he'd been near the spot on I-80 where Zywicki was last seen on the day of the abduction. His brothers and mother lived in the Peru, Illinois, area, and he'd been trying to get a job there.
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Zywicki's case remains listed on both the Illinois State Police and FBI websites. Anyone with information is asked to call the Illinois State Police at 815-726-6377 or the FBI's Chicago office at 312-421-6700, or send a message via tips.fbi.gov.
This article originally appeared on Des Moines Register: Murder of Tammy Jo Zywicki remains a mystery over 30 years later
