U.S. federal prosecutors have launched a criminal probe into opioid producers and distributors to determine if they allowed access to opioids intentionally, The Wall Street Journal reported Tuesday.

The Eastern District of New York has filed subpoenas against at least six drugmaker and distributor companies, including Teva Pharmaceutical Industries Ltd., Mallinckrodt PLC, Johnson & Johnson, Amneal Pharmaceuticals Inc. and AmerisourceBergen Corp. and McKesson Corp.

If the investigation, which is in its early stages, ends in criminal charges it could be the largest prosecution of drug companies over the opioid crisis.

The Controlled Substances Act mandates drug manufacturing and distributing

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