The callers identify themselves as FDA special agents who are cracking down on what they say is illegal purchasing of drugs over the Internet or through "telepharmacies." They then demand that their intended victims pay fines, via wire transfer (often to the Dominican Republic), to avoid prosecution. If the targeted victim refuses, the caller may make additional threats in order to force victims to acquiesce.
I'm sure anyone involved in regulatory issues at your firm has said in jest, following a site visit from the Agency, "Was that really an FDA official, or an impersonator?" All joking aside, this latest scam is a case where the impersonating that is being done is real.