(CNN) -- It's a mystery more than four decades in the making. Two cars -- rusted, caked with mud and carrying as many as six bodies -- pulled from the bottom of an Oklahoma lake.
According to CNN affiliates KFOR and KOCO, Custer County sheriff's deputies weren't looking for the cars Tuesday, but found them anyway when Oklahoma Highway Patrol sonar equipment being used for another purpose revealed their location at the bottom of the reservoir about 150 miles west of Oklahoma City.
Investigators say they believe one car may belong to a teenager who disappeared with two friends in 1970. The other car could be linked to the disappearance of a man in 1969, the stations reported.
Debbie McManamman said she believes the older car, which appears to be a 1950s-era Chevrolet, contains the remains of her grandfather, KFOR reported. The station didn't name the man, and Custer County authorities told CNN early Wednesday that Sheriff Bruce Peoples wasn't available for comment.
"We never gave up, we always wanted some clue that somebody knew something," McManamman told the station.
"It's been very traumatic -- I can remember my dad having dreams at night and getting in the car as soon as he was off from his day job, taking my mom, and they would look and look and look -- any trace," McManamman said.
Peoples told KOCO on Tuesday that the other car, a 1969 Chevrolet Camaro, may have belonged to 16-year-old Jimmy Williams, a Sayre, Oklahoma, teenager who disappeared in 1970 with two friends: Thomas Rios and Leah Johnson, both 18.
The disappearances have long been part of local lore, Sayre resident Mandy Dunlap told KFOR.
"Everybody's just talking about it, you know, can't believe after so many years we're finding those vehicles in a lake," she told the station.
Peoples told KOCO that he hoped the discoveries could help put families at ease about what happened to their loved ones so many years ago.
"It has real importance to the families to determine, so they can have closure and know what happened to their families and have remains and to go on with life now," he said.
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