A lake patrol found the two cars -- each with three skeletons inside -- in Foss Lake while testing new sonar equipment last month.
Investigators said they were awaiting DNA results to confirm the identities of the skeletons, but so far the general descriptions of two separate missing persons cases match what they found in the lake, CNN reported Friday.
One car, a 1969 blue Camaro, matched the description of the vehicle missing 16-year-old Jimmy Williams, of Sayre, Okla., bought just six days before he disappeared with friends Thomas Rios and Leah Johnson, both 18. The teens disappeared en route to a football game in 1970 in Williams' Camaro.
Amy Elliott, chief administrative officer for the state medical examiner's office, said the Camaro found in Foss Lake held the remains of two teenage boys and a teenage girl.
The second vehicle, a 1952 green Chevrolet, matched the vehicle owned by John Alva Porter, 69, who went missing in 1969 along with Cleburn Hammack, 42, and Nora Marie Duncan, 58. The three were last seen purchasing beer together.
The medical examiner's office said the remains inside the Chevrolet found in the lake were that of an "elderly" man, an adult female and an adult male.
"Family reference sample DNA has been collected from all of the presumed families and it has been sent to a DNA reference laboratory," Elliott said in a statement.
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