In a case that has haunted Illinois for more than three decades, authorities are once again delving into the tragic story of a young woman who vanished along her route from the Chicago area to college in Iowa. Investigators from the Illinois State Police are eager for new insights, particularly about a woman who might have interacted with a potential suspect.
Tammy J. Zywicki, a 21-year-old college student, went missing on August 23, 1992. She embarked on a journey from Evanston, Illinois, intending to reach Grinnell College in Iowa, but she never completed her trip.
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Later that day, a state trooper discovered her abandoned white 1985 Pontiac T1000. As dusk settled, her concerned mother reached out to the state police, reporting that Tammy hadn’t arrived at her destination, sparking a frantic search.
Tragically, on September 1, 1992, Tammy’s remains were discovered. She had been brutally stabbed, her body left along Interstate 44 in rural Lawrence County, Missouri, a chilling stretch of highway nestled between Joplin and Springfield.
Witnesses at the time noted a semi-truck parked near Tammy’s car. The truck driver was described as a white male, aged between 35 and 40, towering over six feet tall with conspicuously dark, bushy hair, details that continue to fuel the investigation.
Special agents are now looking for information about Theresa “Teri” Belenske, who may have a connection with the truck driver. ISP said Belenske, whose maiden name is Vega, was known to hitch hike and may have been traveling with the truck driver at some point before Zywicki’s death.
ISP said Belenske is a person of interest, not a suspect. She would have been 32 years old at the time of Zywicki’s death, and she passed away in 2014 at 54 years old.
Special agents are looking for information about Belenske from the late 1980s through the mid-1990s. Belenske has ties to cities in California, including Oceanside, Vista, Pomona, San Bernadino, and Fontana.
Police asked anyone with information about Belenske or Zywicki’s case to leave a crime tip at ISP Investigative Tips page or call 1-800-CALL-FBI. Callers can remain anonymous.
The FBI is offering a reward of up to $50,000 for information leading to the killer’s identification.
Police released a photo of Belenske taken in 2009, along with an AI-generated image of what she may have looked like in 1992.
Police also released photos of Zywicki and some of her property known to be missing.
Missing items include a Cannon 35mm camera and a Lorus brand musical wristwatch, which played the tune “Raindrops Keep Falling On My Head.” Also taken was a red and white soccer patch monogrammed with “St. Giles Soccer Club, Greenville, SC.”
Zywicki’s case remains active as ISP and the FBI continue to explore new leads, examine 200 pieces of evidence, and retest items with modern DNA technology.
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