The 18-year-old was last known to be at the Lansdale Train Station on Nov. 8, 1993, said the District Attorney's Office.
She had taken the R5 SEPTA train in from Philadelphia before calling her father and asking for a ride home at around 11:40 p.m., authorities said.
But when her dad arrived, Julie was nowhere to be found.
Her parents reported her missing the next day, Nov. 9. Little more than three weeks later on Dec. 2, her remains were found in the Lansdale SEPTA/Conrail freight yard.
The autopsy revealed Barnyock died from blunt force head injury and her death was ruled a homicide, according to officials.
“A teenager went missing 30 years ago and was found dead. Our detectives continue to go over this case, looking for anything that could help us. Now we are again asking for the public’s help,” said DA Kevin Steele.
“Someone somewhere knows something. Please share whatever piece of info about Julie’s movements that day, anything seen that night on the train or at the train station," he wrote.
"Many old cases are solved when someone comes forward with information that seems insignificant but turns out to be helpful in finding a murderer."
A $10,000 reward is being offered for information that leads to an arrest and conviction. To submit a tip, call the Montgomery County Detective Bureau at 610-278-3368 or the Lansdale Police Department at 215-368-1801.
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