In what the U.S. Department of Justice called on Thursday the largest health care fraud enforcement action in the agency’s history, more than 400 defendants nationwide have been charged with defrauding taxpayers of $1.3 billion.

The takedown—which is the largest enforcement action of its kind in terms of number of defendants, though not in terms of dollars— is a strong reflection of one of the new announced priorities at the DOJ under the Trump administration and new U.S. Attorney General Jeff Sessions: drugs, particularly opioid painkillers and other prescription narcotics.