Updated

The shocking slaying of two young Bible-camp workers found shot in the head on a Northern California beach more than a decade ago may finally be solved, officials said Friday.

The young couple, Lindsay Cutshall, 22, and her fiance Jason Allen, 26, was found next to each other on a driftwood-strewn beach, still zipped into their sleeping bags, on Aug. 18, 2004.

On Friday, Sonoma County Sheriff Steve Freitas said investigators have interrogated Shaun Gallon, 38, of Forestville, who is in custody in the March fatal shooting of his brother. Gallon knew things about the killings that no one who wasn't involved could have known, the sheriff said, and authorities have also found corroborating evidence.

"We feel confident we have Jason and Lindsay's killer," Freitas said of the young couple, whose mysterious killings drew national attention.

No one has ever been charged in the killings, and no motive has ever been made public. Authorities have said neither victim was robbed or sexually assaulted. Freitas said authorities believed the killing was random, and that there was no previous connection between the two and the suspect.

Cutshall, a native of Fresno, Ohio, and Allen, from Zeeland, Michigan, were on a weekend trip. They worked at a Christian youth camp in California's Sierra Nevada foothills.