And police said Wednesday night they were looking for a ninth suspect who was to have disabled the surveillance system at the couple's home but never did.
Pamela Long Wiggins, 47, was found in Orange Beach, Ala., Wednesday and returned to Florida, Escambia County Sheriff David Morgan said.
She was to be charged as an accessory after the fact to felony murder because she was not at the couple's sprawling home when the home invasion, robbery and slayings happened July 9, ABC News quoted Morgan as saying.
Wiggins, who police said used several aliases, had rented property to one of the seven males.
Before announcing she had been found, CNN reported, Morgan held up a photo of Long and said, "We believe Ms. Long has significant and substantial information we need to conclude this case."
Morgan said police were seeking a ninth suspect in the deaths of Byrd and Melanie Billings, the Beulah couple well-known in the Florida Panhandle as the parents of 17 children, 13 of them adopted, many of them with special needs.
The first seven suspects arrested allegedly had trained with weapons, sported ninja-style outfits and plotted the night-time assault on the nine-bedroom home with military precision, the St. Petersburg (Fla.) Times reported Wednesday.
One suspect, Leonard Gonzalez Sr., owned a power-washing company and had worked at the home, Morgan said. Two suspects had military training, and Morgan said the men had been trained to perform as a militia.
CNN also reported Wednesday the Drug Enforcement Administration confirmed it is assisting in the investigation.
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