Updated

Back in 1971, two South Dakota teens vanished on their way to a party. Now the 43-year-old mystery of their disappearance has been solved by the ebb and flow of a dirty creek and the contents of a well-preserved purse.

When Cheryl Miller and Pamella Jackson didn't show up at the roadside gathering, classmates just assumed they had changed plans, perhaps to avoid any underage drinking or pot smoking.

Their car was finally found in September after a fisherman saw two tires sticking above the water in a creek. Inside, authorities found human remains and Miller's purse with her driver's license.

Authorities confirmed this week that the remains inside belonged to the girls.

A former police officer believes the pair accidentally drove into the water in the dark.