CAMDEN, N.J. (AP) — Authorities say a police officer and three firefighters are among seven people recently charged in a $50 million prescription drug scheme that has already produced nearly two dozen guilty pleas.

The U.S. attorney’s office announced the indictment Friday in Camden, New Jersey.

The defendants allegedly used a network of recruiters, doctors, and state and local employees to get reimbursed for phony prescriptions and expensive and medically unnecessary compounded medications.

Authorities say the scheme exploited the fact that some public worker benefits programs offered reimbursement for the expensive medications.

The defendants were scheduled to appear in court in Camden for an initial appearance Friday.

Twenty-three people already have pleaded guilty, including a doctor who admitted signing prescriptions for patients he never saw as part of the scheme.