More than 400 people, upwards of 120 individuals involved in prescribing and distributing narcotics, have been charged in connection with healthcare fraud and opioid scams totaling $1.3 billion in false billing.

Announcing the charges on Thursday, Atty. Gen. Jeff Sessions calls it the "largest healthcare fraud takedown operation in American history."

Six Michigan physicians are among those charged in connection with a scheme to prescribe unnecessary opioids.

"Too many trusted medical professionals like doctors, nurses, and pharmacists have chosen to violate their oaths and put greed ahead of their patients," Sessions said in announcing the arrests.

"Their actions not only enrich themselves, often at the expense of taxpayers, but also feed addictions and cause addictions to start."

As part of the crackdown, Sessions says nearly 300 healthcare providers are being suspended or banned from participating in federal healthcare programs.

In Florida, a rehabilitation facility is alleged to have recruited addicts with gift cards and visits to strip clubs, which led to $58 million in false treatments and tests.

According to a Department of Justice press release, another illegal clinic in Houston allegedly handed out prescriptions for cash. One physician at this clinic allegedly gave out 12,000 opioid prescriptions for over 2 million illegal doses of painkillers.