DUBUQUE, Iowa — An over 30-year-old missing person case is one step closer to being solved after a car was discovered in the Mississippi River earlier this month.

Paul Joseph Knockel, 53, was reported missing by his family in Dubuque on Nov. 25, 1990 — nearly 33 years ago. According to Iowa Cold Cases, Knockel was last seen on Nov. 12 and his car was last seen on Nov. 13 parked along Highway 151, near the Dubuque-Wisconsin Bridge. The Dubuque Police Department said his case has remained open ever since.

On Oct. 12 this year employees from Newt Marine Services found a submerged vehicle while conducting dredge operations near the Hawthorne Boat Ramp. Investigators with the police department processed the vehicle, a 1981 Mercury Zephyr, and were able to identify it as belonging to Knockel. No human remains were located during the investigation.

Anyone with information about Knockel’s disappearance can submit anonymous tips online on the police department’s official site or by calling Dubuque Crime Stoppers at (800)747-0117.