The U.S. Justice Department has criminally charged 193 people, including 76 doctors, nurses and other medical professionals, with participating in health care fraud schemes worth $2.75 billion, the agency said today.

The two-week operation ensnared defendants accused of illegally distributing millions of pills of the stimulant Adderall. It also included $176 million in fraudulent schemes involving drug and alcohol abuse treatment, including one defendant accused of billing the federal Medicaid program for treatment that was either inadequate or nonexistent, Attorney General Merrick Garland said.

The bust also targeted schemes involving telemedicine, charging 36 defendants accused of collectively submitting over $1.1 billion in false claims to the U.S. Medicare program.

“The Justice Department will bring to justice criminals who defraud Americans, steal from taxpayer-funded programs, and put people in danger for the sake of profits,” Garland said during a press conference.

The government seized more than $231 million in cash, luxury vehicles, gold and other assets in the law enforcement action that spanned 32 federal districts.

In one scheme, federal prosecutors charged seven people associated with the San Francisco-based telehealth startup Done Global with illegally distributing Adderall, a stimulant used to treat attention deficit hyperactivity disorder, commonly known as ADHD.

One nurse practitioner at the company was accused of prescribing 1.5 million pills of Adderall while having little interaction with patients. The company’s founder and top doctor were charged earlier this month.

U.S. officials said fraud schemes may have played a role in well-publicized shortages of Adderall in recent years.

A spokesperson for the company did not immediately respond to a request for comment.

The investigations were led by the Justice Department’s criminal fraud unit and involved the Department of Health and Human Services Office of Inspector General, FBI and Drug Enforcement Administration.

Officials said they have increasingly relied on data analytics to spot fraud schemes that either put patients at risk or cost the U.S. government.