Florida Couple Slaying Suspects dressed in Ninja Garb

Criminals dressed in Ninja Garb may be the prime suspects in the slaying of a Florida couple.

Investigators were hoping for more arrests today in the shooting deaths of a Florida Panhandle couple who had adopted a dozen children with autism, Down syndrome and other disabilities.

Authorities made three arrests over the weekend and a fourth Monday evening. Escambia County Sheriff David Morgan said he hoped to make one or two arrests today. Morgan told ABC's ''Good Morning America'' that authorities have tied at least seven people to the crime but that nothing links any of the suspects to the family directly.

Morgan said day laborer Gary Lamont Sumner was arrested on a murder charge in a nearby county Monday after he was pulled over in a traffic stop. The sheriff said investigators have placed Sumner at the scene of the killings of Byrd and Melanie Billings, though he wouldn't provide details.

The couple took care to make their nine-bedroom house a safe place for their growing brood of children, wiring it with surveillance cameras in every room.

It was those cameras that captured images of the masked men who shot the wealthy couple Thursday in a break-in executed with chilling precision.