The Houston couple, whose identities have not been released, said they believed they were purchasing roughly 100 storage cases for guns via a resell on eBay, according to a report.
"It's just a case, everybody can buy it online," one member of the couple said.
However, when one of the cases was opened, the pair found at least one dozen fully automatic M16s.
The M16 is strictly designed to be used by the military, the report noted.
The couple reported the find to the authorities.
