The operation led to criminal charges against 324 defendants and the seizure of more than $245 million in cash, luxury cars and other assets.

State and federal prosecutors have charged more than 320 people in the largest coordinated takedown of health care fraud schemes in Justice Department history that uncovered nearly $15 billion in false claims.

Matthew Galeotti, head of the justice department’s criminal division, called the operation “the beginning of a new era of aggressive prosecution and data driven prevention” of healthcare fraud.