WASHINGTON (AP) — The Justice Department on Tuesday announced criminal charges against 455 people as part of a two-week healthcare fraud crackdown that officials say involved more than $6.5 billion in false claims submitted to insurers.

Among those charged is a nurse practitioner accused in Texas of billing Medicaid for medically unnecessary wound-care procedures and using the proceeds for fancy jewelry and luxury cars; a mental health company owner who prosecutors say exploited the homeless by billing for crisis stabilization services they did not need; and a hospice owner alleged to have paid kickbacks to a funeral home employee for information about Medicare beneficiaries.

A heart doctor is charged in Florida in an $89 million healthcare fraud scheme, accused of billing insurers for medically unnecessary cardiovascular screening tests for college student-athletes and then rubber-stamping the results as normal without reviewing them.

Jason Finkelstein, 53, faces charges in Florida of healthcare fraud and conspiracy in what prosecutors describe as a yearslong scheme that preyed on the fears of athletes that they could die on playing fields or courts of sudden cardiac arrest.

Athletes with no preexisting conditions who were concerned about being cleared to compete were administered tests they did not need and, in one case, a patient whose results were falsely certified as normal later died after his significant heart problems were undetected, the indictment says.

Healthcare fraud has been a long-running Justice Department priority and news conferences announcing mass roundups and crackdowns have been common occurrences across the years. The Trump administration has sought to emphasize fraud enforcement over the last year, including through the appointment of a new assistant attorney general, Colin McDonald, to help oversee healthcare fraud prosecutions at a Justice Department that operates multiple specialized task forces.

"Today's cases allege more than the theft of taxpayer dollars. Many allege the theft of human dignity," McDonald said at a news conference announcing this year's crackdown, which covers cases charged or unsealed since June 8. "Our sick, needy and elderly placing their faith in the gift of medicine were neglected, ignored and used for personal profit,"

The department says Finkelstein's case, with allegations not only of unrendered services but also poor medical performance that put patients at risk, represents the type of sophisticated scheme prosecutors are striving to disrupt.

A lawyer for Finkelstein, a Texas-based doctor who pleaded not guilty during a court appearance in Florida on Monday, did not return messages seeking comment.

The alleged fraud ran between 2019 and the end of last year and, prosecutors say, involved Finkelstein and a pair of unidentified co-conspirators at a Florida-based cardiovascular testing and treatment practice that he owned and operated.

Officials say the scheme had multiple components, with Finkelstein and his company using what the indictment says were deceptive marketing tactics to offer free heart screens for students who did not need them and then certifying the results of the tests as normal without reviewing them — and even when they turned out to reveal potential problems.

The indictment quotes Finkelstein as telling an unnamed co-conspirator with whom he worked that "(t)hese kids could be high risk ...(o)ne of them drops dead on a field, they're coming after both of us."

Finkelstein's co-conspirators blasted out emails to athletic trainers at colleges and universities stating that the tests being offered could identify any life-threatening condition that could prevent the students from playing, and also offered kickbacks and other inducements to school officials to refer potential patients, according to the indictment.

Insurance companies do not cover blanket cardiovascular testing but instead require a prior finding of a medical necessity. To avert that roadblock and secure reimbursement, prosecutors say, Finkelstein submitted to insurers phony diagnoses of conditions, such as elevated blood pressure and hypertension, that the athletes did not actually have.

His company relied on sonographers who lacked the requisite credentials to travel to college campuses to perform the tests, and because Finkelstein was licensed in the 48 contiguous states, he and his company were able to submit claims for patients across the country, the indictment says.

At the same time, prosecutors say, Finkelstein would certify cardiac test results as being normal without actually reviewing them. In one instance in 2024, according to the indictment, he signed off after roughly 11 seconds on approximately 63 test result images of one patient. The test results actually revealed a significantly enlarged heart and the teenage patient later died on the basketball court, officials said.

"There is no way they could miss that, except they didn't care," said Mehmet Oz, a cardiothoracic surgeon by training and head of the Centers for Medicare & Medicaid Services. "This is not a diagnostic company. It's a predatory scheme dressed up in medical clothing and we're going to treat it as such."