ST. CHARLES, Mo. -- Nancy Kitzmiller was a 24-year-old employee working at Boot Village in 1992 at Bogey Hills Plaza when her dead body was tragically found in the back room of the store by customers.

Kitzmiller had graduated from the Fort Zumwalt School District and recently finished schooling at Oklahoma State University.

According to the St. Charles Police Department, her death was ultimately linked to the murders of six other women along Interstate 70 across Indiana, Missouri, and Kansas.

Over 30 years ago, an unidentified serial killer known as the "I-70 Killer" traveled along the interstate, killing multiple women with the same murder weapon and ammunition.

Now, 33 years later, the search for that serial killer is still ongoing.

According to the St. Charles Police Department, the suspect was described as a white male, aged mid-20s to mid-30s in 1992. Today, the unknown killer is suspected to be in his mid-50s.

The suspect was also described to be 5 feet 7 inches tall, weighing 140 to 160 pounds, with light brown to red hair and beard stubble on his face.

The suspect allegedly began his murder spree on Apr. 8, 1992, in Indianapolis, Indiana, when he killed a 26-year-old woman named Robin Fuldauer at a Payless shoe store.

Three days later, the suspect killed 32-year-old Patricia Magers and 23-year-old Patricia Smith at La Bridal shop in Wichita, Kansas.

Later that month, 40-year-old Michael McCown was killed in his shop, Sylvia's Ceramics, in Terre Haute, Indiana. Police said McCown was the only male victim in the series of deaths.

Police state that the suspect potentially mistook McCown for a woman due to his long hair after allegedly watching the victim from outside the ceramics shop.

The suspect then headed to St. Charles, Missouri, where he took the life of Kitzmiller at Boot Village. Then four days later, he murdered 37-year-old Sarah Blessing at the Store of Many Colors in Raytown, Missouri.

FOX 2 reported that police said he used an unusual weapon that has been linked to five other murders. Officials say, based on ballistic evidence and witness statements, the gun was a 22-caliber, possibly an Intratec Scorpion or an Erma Werke Model ET 22.

For years, officials have been asking gun collectors and dealers to notify them if they see such a weapon or had one stolen in the early 1990s.

The most recent advancement in the cold case was in 2021 when FOX 2 reported five different police departments met with the Federal Bureau of Investigation to review evidence with advances in forensic technology.

There is a $25,000 reward that is still being offered for information involving the case. Anyone with information is asked to call the St. Charles, Missouri, police at 636-949-3200.