() Members of a dive team scouring the Chicago River for clues in a missing persons case say they have found about 140 cars in the water.

The renewed search for the couple at the heart of a 50-year-old cold case has captured the interest of Chaos Divers, a sonar search and recovery team committed to providing answers to families of the missing.

Edward and Stephania Andrews were a married couple from Arlington Heights, Illinois, who disappeared on May 15, 1970.

“We receive significant support from law enforcement when they know we’re on the scene,” stated Chaos Divers founder Jacob Grubbs. “We strive not to trouble them excessively, as we are capable of searching and diving for these vehicles. When we do reach out to law enforcement, they are incredibly cooperative.”

The Chicago Tribune states that the couple was headed home in their yellow 1969 Oldsmobile after leaving a cocktail party at the Sheraton Hotel downtown, but they never arrived.

The couple was reported missing the following Monday, but 55 years later, the mystery surrounding their whereabouts remains.

A renewed effort to locate them in 1994 provided investigators with few answers.

Grubbs said he only hopes that his work brings closure to families.

“Everyone deserves to know what happened to their lost loved one when they disappeared. Being able to provide answers to a family is an indescribable feeling for us, and I am certain it is so for the family as well.”

affiliate WGN-TV in Chicago contributed to this report.