Tammy Zywicki was last seen alive, police say, 20 years ago today near LaSalle, Ill., after her car broke down along Interstate 80. Her body, wrapped in a blanket sealed in duct tape, turned up nine days later in Southwest Missouri.
Now two decades later, the killer remains elusive, and federal and Illinois investigators hope a $50,000 reward throws some light on the subject. On Wednesday, the eve of the 20th anniversary of Zywicki’s disappearance, the head of Illinois State Police insisted that investigators haven’t forgotten the vexing case.
“This investigation remains a top priority, both for me personally as well as the men and women” of the agency, State Police Director Hiram Grau said. He said authorities “are committed to bringing justice and peace to the Zywicki family.”
Robert Grant, the head of the FBI’s Chicago office, touted the reward from a source authorities have not disclosed. He said he hopes a tipster supplies details “needed to bring this investigation to a close.”
“We remain confident that someone knows who committed this heinous act and will have the courage to help us identify this individual,” Grant said.
FBI spokesman Ross Rice told the Globe by telephone Wednesday from his Chicago office that a reward for information in Zywicki’s case has been offered by the FBI for years.
“The case is unsolved, and we’re still looking for the person or persons responsible,” he said.
Zywicki, 21, was returning to Iowa’s Grinnell College, where she would have been a senior, from her home in Marlton, N.J., on Aug. 23, 1992, when her Pontiac broke down along the interstate. Some witnesses later said a tractor-trailer was seen parked behind her car. Others said they saw a pickup truck.
Her body was found more than a week later in the grass near a westbound ramp on Interstate 44, about 11 miles west of Mount Vernon. She had been stabbed multiple times in the chest.
A task force headed by the FBI and Illinois State Police spent months chasing hundreds of leads “without success” before disbanding, Wednesday’s statement from those two agencies said.
Over the past two decades, investigators have looked at truckers suspected in killings and sexual attacks elsewhere but eventually eliminated them from suspicion in Zywicki’s death.
Authorities had specifically focused on Bruce Mendenhall, a trucker who was arrested in 2007 and suspected of fatally shooting women in several Midwest states, and Lonnie Bierbrodt, an ex-convict trucker who was from the area where Zywicki was last seen alive and who died in 2002.
NO ONE HAS EVER been charged with the August 1992 murder of 21-year-old Tammy Zywicki.