The complaint alleges that the retail pharmacy filled prescriptions for controlled substances that lacked legitimate medical purpose or were not valid.

The U.S. Department of Justice announced a lawsuit on Wednesday accusing pharmacy chain CVS of filling illegal opioid prescriptions and billing federal health insurance programs, contributing to a nationwide epidemic of opioid addiction and overdose.

CVS (CVS) and its subsidies unlawfully dispensed “massive quantities” of opioids and other controlled substances over more than a decade, according to the Department of Justice.