A woman has pleaded not guilty to first-degree murder in the mysterious slaying of a Camp Pendleton Marine's wife.

Jessica Lynn Lopez entered her plea Thursday after being charged in the death of 22-year-old Brittany Dawn Killgore.

A judge set bail at $3 million during the hearing in the San Diego suburb of Vista.

A prosecutor said authorities found the 25-year-old Lopez with a suicide note Tuesday at a hotel in San Diego.

Within hours, they discovered the body of Killgore in brush near a Southern California lake.

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