A fisherman thought he spotted a car in the Mississippi River. He may have just helped solve a cold case from 1967

Two Minnesota fishermen made an unexpected discovery beneath the Mississippi River this week when sonar technology led them to what authorities say could be a break in a decades-old cold case.

Brody Loch, one of the fishermen, told CNN affiliate WCCO he spotted a car in the river using his sonar device last weekend. Three days later on Wednesday, divers located the vehicle and found human remains inside, Stearns County Sheriff Steve Soyka told CNN.

“It was 100% luck, if my buddy wouldn’t have caught that walleye, we would have kept on floating down (the river) and never would have found it,” Loch told WCCO.

Soyka said he feared the car, a 1960s-era Buick, might break apart if it was brought to the surface, given how long the vehicle had been submerged. But when investigators pulled th