Authorities say a Washington state couple whose bodies were found this week after being missing since April were both shot to death.

The Snohomish County Medical Examiner's office said Thursday that Monique Patenaude, 46, died of multiple gunshot wounds. Her husband, 45-year-old Patrick Shunn, died of a gunshot wound to the head.

Officials say Tony Clyde Reed, one of two brothers charged with the slayings, provided information that led detectives to pinpoint the location of the bodies about 50 miles northeast of Seattle on Tuesday. He turned himself in last week at the U.S.-Mexico border after a monthlong manhunt. Authorities are still searching for Reed's 53-year-old brother, John Blaine Reed

Authorities had been searching for the couple since they were reported missing April 12.

John Reed had threatened to shoot the couple for cutting brush between their two properties in 2013, according to court documents.

Tony Reed has pleaded not guilty pleas to two counts of first-degree murder and unlawful firearm possession in the case.

His attorney, James Kirkham, helped arrange the surrender. Kirkham told The Daily Herald in Everett, Washington, on Monday that his client turned himself in to answer the allegations against him.

"My client is innocent of the first-degree murder charges," the lawyer said.

John Reed lived up an old logging road from the couple's 21-acre spread in the foothills of the Cascade Mountains. When Patenaude and Shunn sued other neighbors over a property dispute more than two years ago, they avoided naming him as a defendant because they didn't want to irk him, their former lawyer, Thomas Adams, said previously.

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