25 years later, police still seek clues in 1992 murder of college student

Wednesday marks the 25th anniversary of one of Illinois' most nagging cold cases. The FBI and Illinois State Police said the investigation into the day a 21-year-old college student from New Jersey left north suburban Evanston en route to a small college in Iowa, but never made it, remains active, and they continue to explore new leads.

Investigators are even in the process of retesting evidence for DNA in hopes of bringing closure to Tammy Zywicki's family. A $50,000 reward is being offered for information in the case.

"It's the death of an innocent kid, driving to college. Brutally murdered. That's should not happen," said Garrett Croon, FBI.

A senior at Grinnell College in Iowa, Zywicki had just dropped her younger brother off at Northwestern University in Evanston and was on her way back to school when her car broke down on I-80 near Utica. That was the last time she was seen alive. Her body was found nine days later, wrapped in a blanket off the side of the road hundreds of miles away in Missouri. She had been stabbed to death.

Throughout the years there have been suspects, but no arrests. Dozens of investigators have come and gone.

Police also reported that a semi truck was seen near her car, but do not know if it was involved in her disappearance and death. The driver was described as a white male 35-40, over 6 feet tall, with dark, bushy hair.

A convicted felon who died in 2002 was once considered a person of interest in the case, but authorities said after being investigated, they do not believe he was the killer.

"Maybe this guy is dead who killed her. Maybe he's sitting on a couch. Maybe he's in jail> but he should have told someone," Croon said.

And that's what investigators hold on to: the possibility that someone out there knows something and will come forward.

The FBI released new information and pictures on their website Tuesday, including of a soccer patch that may have been in Zywicki's possession at the time of her disappearance.

"Look at that information. Look at those photographs. Does that jog something in your head, 'Hey, I remember that. I remember someone showed it to me.' That's what we're looking for," Croon said.

Authorities are also looking for items of the victim's personal property, including a Cannon 35mm camera and a Lorus brand musical wrist watch which played the tune "Raindrops Keep Falling On My Head," with a green umbrella on its face and a green band, ISP said.

Anyone with information is asked to contact the ISP at (815) 726-6377, or the FBI Chicago Field Division at (312) 421-6700. Callers can remain anonymous.

Click here for more information from the FBI.

The Sun-Times Media Wire contributed to this report.
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