() 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 center of a 50-year-old cold case has caught the attention of Chaos Divers, a sonar search and recovery team dedicated to bringing 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 do have a lot of support from law enforcement when they know that we’re there,” Chaos Divers founder Jacob Grubbs told . “We try not to bother them as much, due to the fact that we can search and dive for these vehicles. When we reach out (to law enforcement), they are just amazing to work with.”

The Chicago Tribune reports that the two were headed home in their yellow 1969 Oldsmobile after leaving a cocktail party at the Sheraton Hotel downtown, but they never made it.

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.

“Everybody is supposed to know what happened to the lost loved one when they went missing. When we’re able to bring answers to a family, it’s an indescribable feeling for us, and I know it is for the family.”

affiliate WGN-TV in Chicago contributed to this report.