Families and friends who have wondered since 1971 about what happened to two South Dakota girls now have some closure.

Authorities said Tuesday that they believe Pamela Jackson and Cheryl Miller died when their 1960 Studebaker Lark accidentally went off a gravel road and into a local creek. "All the evidence would appear to indicate an accident," South Dakota Attorney Gen. Marty Jackley said.

Among the clues, according to Sioux Falls' Argus Leader: The car "was in third gear, with the keys in the ignition and the lights on. One tire was damaged. ... Miller's purse was found, Jackley said. Inside it was her license, notes from classmates and photographs."

The girls had been on their way to a party that teens were having at a gravel pit. Their car wasn't discovered until last September, when low waters in the creek revealed the rusted wreck.

The Sioux City Journal adds that:

"The car did not contain any evidence, such as cans or bottles, that alcohol was involved. Based on witness accounts, the girls, who visited Miller's grandmother in the hospital in Vermillion, then met up with friends and followed them to Alcester, wouldn't have had time to stop along the way, Jackley said. ..."The bridge was new, which might have confused the girls. One of the Studebaker's tires was damaged, but officials don't know if that happened before or after the crash. ..."Classmates thought the girls were behind them but lost sight of the Studebaker. 'They had indicated they were being followed by the girls (and) that at one point they had missed the turn and then they looked back and the girls had vanished,' Jackley said."An extensive search of the area didn't reveal anything, and their families were left to agonize about what may have befallen them. The case confounded local law enforcement."

At one point in 2007, as we have reported, a man was indicted on murder charges related to the girls' deaths. But the charges were dropped when investigators determined that a recording of the suspect's alleged jailhouse confession had been faked by another inmate.

Both Jackson and Miller, who has also been referred to in news accounts as Sherri, were 17 years old. They were students at Vermillion High School.

Last September's discovery of the Studebaker, which had apparently been submerged in the creek's waters for more than four decades, came one week after a similar story from Custer County, Okla. There, as we wrote, "sheriffs' deputies who were testing a new sonar device on a lake in western Oklahoma's Custer County [came] across two grim discoveries." They found two cars in Foss Lake — each with three bodies inside. One vehicle and its adult occupants had been missing since 1969. The other vehicle and the three teenagers inside disappeared in 1970.

Authorities are still trying to determine how those vehicles ended up in that lake.

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