Updated on: May 5, 2017 / 4:44 PM / CBS/AP

SONOMA COUNTY, Calif. -- Sonoma County Sheriff Steve Freitas says a suspect is in custody in the killings of a young couple on a Northern California beach more than a decade ago.

He says 38-year-old Shaun Gallon of Forestville was arrested recently in the killing of his brother. The sheriff said Gallon was "well-known to authorities" and that he was a person of interest in the Jenner case, reports CBS San Francisco. 

Questioned about the 2004 killings while in custody now, Gallon had relayed "information about the killings that no other person could have known," the sheriff said of the 2004 case. Authorities have since found further corroborating evidence, he said.

The killings and the mysteries surrounding them long had drawn national attention: The bodies of 22-year-old Lindsay Cutshall and her 26-year-old fiance Jason Allen were found next to each other on a driftwood-strewn beach near Jenner, California, on Aug. 18, 2004. They were scheduled to be married a month later.

The sheriff says "we feel confident we have Jason and Lindsay's killer."

The two Christian youth-camp workers were still zipped into their sleeping bags, and authorities believe they were shot in the head as they slept.

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

Authorities have said neither victim was robbed or sexually assaulted.

Gallon was arrested and charged with murder on March 25 for the shooting death of his 36-year-old brother. 

Investigators say Gallon shot his brother in the home they shared with their mother in Forestville, a rural community 66 miles north of San Francisco. 

Police say they recovered an assault-style rifle they believe Gallon assembled. He is being held in Sonoma County jail without bail, but he has not yet been charged in the beach killings, Freitas said.

No motive in the 2004 case has ever been made public. Freitas said authorities believed the killing of the young couple was random, and that there was no previous connection between the two and the suspect.

Authorities previously said they also were still trying to find a motive in the shooting death of Gallon's brother, Shamus, saying there was no known conflict between the two before the shooting.

In a statement read by the sheriff, the dead couple's parents thanked law enforcement, whose "humanity and professionalism would not allow them to give up the case."

The parents' statement also offered prayers for the suspect "who heartlessly committed this crime" and for the people around the beach town of Jenner, who had described themselves as haunted by the case.

First published on May 5, 2017 / 2:13 PM

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