The arrests came as part of what the department said was the largest healthcare fraud takedown in US history and included 162 doctors and other suspects charged for their roles in prescribing and distributing addictive opioid painkillers.

“In many cases, doctors, nurses, and pharmacists take advantage of people suffering from drug addiction in order to line their pockets,” Attorney General Jeff Sessions said in a statement. “These are despicable crimes.”

The charges centred in part on schemes to bill the government healthcare programs Medicare, Medicaid and Tricare as well as private insurers for medically unnecessary prescription drugs and compounded medications.

The Justice Department also brought charges against medical professionals it said were contributing to the country’s opioid epidemic by participating in the unlawful distribution of prescription painkillers.

In 2016, 42,000 people in the United States died from opioid overdoses, according to the US Centers for Disease Control and Prevention.

“The perpetrators really are despicable and greedy people,” US Health and Human Services Secretary Alex Azar said at a press conference.