McHugh was unsure why the suspects resorted to violence against the elderly couple.
"We don't know why," he said. "From everything we've found so far there's no evidence that [the Ewings] fought back. It's certainly bewildering to us why they beat them like they did."
McHugh said they aren't used to encountering such violence in their community.
"We don't have a lot of violent crimes against persons here in Loganville," he said. "Something of this magnitude is very unusual."
-- Staff reporter Christian Boone contributed to this report.