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One of the country’s largest pharmacy chains knowingly filled unlawful prescriptions and ignored internal red flags on its practices, the Justice Department alleged in a complaint filed Monday.

The complaint against Rite Aid was part of a whistleblower lawsuit brought against the company under the False Claims Act and the Controlled Substances Act, the Justice Department said in a news release.

From May 2014 until June 2019, the federal government claims Rite Aid “filled at least hundreds of thousands of unlawful prescriptions for controlled substances that were medically unnecessary, lacked a medically accepted indication, or were not issued in the usual course of professional practice.”

CBS News has reached out to Rite Aid for comment.

The prescriptions included substances such as a “trinity” combination of an opioid, a muscle relaxer and a benzodiazepine, as well as fentanyl and oxycodone. The latter included prescriptions being filled before prior prescriptions had run out, according to the complaint.

Authorities also said Rite Aid’s Government Affairs Department was aware that its pharmacists were ignoring “obvious red flags,” and that it directed employees in another department to delete internal notes about suspicious activities such as “cash only pill mill???” “writing excessive dose[s] for oxycodone,” and bluntly “DO NOT FILL CONTROLS,” according to the complaint.

Rite Aid has more than 2,200 locations across 17 states including California, Ohio, Oregon, New York, Pennsylvania and Virginia. Its retail pharmacy revenue is expected to be about $17.5 billion for the 2023 fiscal year, according to its latest third-quarter results report.