At least 91 people were arrested in Miami; Houston; Baton Rouge, Louisiana, and four other cities on a variety of charges: from submitting false billing for home healthcare, mental health services, HIV infusions and physical therapy to money laundering and receiving kickbacks.

Justice Department and Health and Human Services Department officials were unable to say how much Medicare actually paid out, but a review of 34 complaints and indictments found that authorities were seeking to recover at least $59.5 million of allegedly ill-gotten gains.

"These fraud schemes were committed by people up and down the chain of healthcare providers - from doctors, nurses, and licensed clinical social workers, to office managers and patient recruiters," said Lanny Breuer, assistant attorney general for the Justice Department's criminal division.

President Barack Obama's administration has been pushing to squeeze out fraud from federal programs like Medicare as part of a broader attempt to stem soaring healthcare costs, arguing fraud can contribute to rising prices for services.

Breuer said that it is the single largest Medicare billing fraud sweep by the Justice Department's special task force in its five-year history. In September, the Obama administration charged 91 people in connection with a variety of schemes aimed at bilking Medicare out of $295 million.

The FBI said it is investigating more than 2,600 cases of healthcare fraud with more than 500 agents and analysts. Since March 2007, the Justice Department said, it has charged more than 1,300 people for falsely billing Medicare more than $4 billion.

Health and Human Services Secretary Kathleen Sebelius sought to use the arrests to defend Obama's controversial healthcare law passed in 2010, arguing that additional resources provided under the law helped authorities root out fraud.

"Today's actions are another example of how the Affordable Care Act is helping the Obama administration fight fraud and strengthen the Medicare program," Sebelius said.

Republicans and 26 out of the 50 U.S. states have challenged the law and are seeking to have it invalidated as unconstitutional because it would require Americans to have health insurance coverage or pay a penalty.

SEVEN ARRESTED IN BATON ROUGE

The biggest cases were in Baton Rouge where seven people were arrested and charged with eight counts, including conspiracy and healthcare fraud for billing Medicare for some $225.6 million in unnecessary services and in some cases not providing services billed.

They ran and worked at two community mental health centers in Louisiana where they billed for more group therapy sessions than were provided, including recreational and education psychotherapy, according to court records.

Medicare paid out more than $37.9 million for the services to the two centers in Baton Rouge, identified as Shifa Community Mental Health Center and Serenity Center, according to the records.

U.S. prosecutors sought to have two of the owners of the centers, Hoor Naz Jafri and Roslyn Dogan, held without bond pending trial. Dogan was also accused of stealing evidence from the prosecutors' office in a bid to obstruct the investigation, according to a detention memo.

Four others who worked as therapists at the centers pleaded guilty last month to one count of conspiracy to commit healthcare fraud for purporting to provide group therapy and document patients' attendance, the court documents said.

In one case out of Miami, 10 people were charged with allegedly seeking $63 million in reimbursements from Medicare as some therapists altered their paperwork to try to justify services for patients who did not need them.

In another Florida case, one person was accused of receiving kickbacks to refer patients to a company that offered home health and physical therapy services, submitting $60 million in claims. Medicare reimbursed that group, NANY Home Health Inc, $40 million.

Last month, the three operators of NANY Home Health were sentenced to lengthy prison terms for their roles in the scheme and were ordered to pay $40 million in restitution.

(Editing by Jackie Frank and Mohammad.zargham)

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