The Department of Justice (DOJ) this week announced a suit against Rite Aid, alleging the pharmacy chain knowingly filled unlawful prescriptions for controlled substances, including opioids.

Rite Aid is one of the country’s largest pharmacy chains, with more than 2,330 pharmacies in 17 states, Reuters reports. The DOJ said the company knowingly filled at least hundreds of thousands of unlawful prescriptions for controlled substances from May 2014 to June 2019 that were medically unnecessary for off-label use.

The suit alleges the unlawful prescriptions included those for a combination of opioids, benzodiazepines and muscle relaxants known as “the trinity,” issued by prescribers whom Rite Aid pharmacists had repeatedly identified internally as writing illegitimate prescriptions.

“We allege that Rite Aid filled hundreds of thousands of prescriptions that did not meet legal requirements,” Associate Attorney General Vanita Gupta said in a news release. “According to our complaint, Rite Aid’s pharmacists repeatedly filled prescriptions for controlled substances with obvious red flags, and Rite Aid intentionally deleted internal notes about suspicious prescribers. These practices opened the floodgates for millions of opioid pills and other controlled substances to flow illegally out of Rite Aid’s stores.”