US. cities on Tuesday with Medicare fraud schemes that the government said totaled $223 million in false billings, Reuters reported. More than 400 law enforcement officers including FBI agents made arrests of 89 suspects who posed as physicians and scammed the $590 billion health-care program with phony or unnecessary bills. About one in four defendants was a doctor, a nurse, a physical therapist or another kind of medical professional.

"In many of these alleged schemes, the fraudulent billings could not have occurred without a doctor signing off on bogus services, or a nurse or therapist filling out false paperwork," Acting U.S. Assistant Attorney General Mythili Raman told reporters. Officials said the action was the sixth "national take-down" by the government's Medicare Fraud Strike Force, which has arrested more than 1,500 people on charges related to $5 billion in allegedly false Medicare claims since 2007.

The Obama administration put a priority on combating fraud, waste and abuse in the Medicare program for the elderly and disabled as a way to restrain government health-care spending and its impact on the federal budget deficit, Reuters reported.

Attorney General Eric Holder, who faced increased questions about why the IRS' role in targeting conservative groups, warned that the anti-fraud effort could be hampered by automatic across-the-board budget cuts known as sequestration, which he said has reduced the Justice Department's budget by $1.6 billion this year.

"Unless Congress adopts a balanced deficit reduction plan and stops the reductions currently slated for 2014, I fear our capacity to protect the American people from health-care fraud, to safeguard vital programs and precious resources and to hold criminals accountable will be further reduced," Holder said. "Allowing these cuts would be both unwise and unacceptable," he added.

In Miami, 25 defendants were charged in schemes totaling $44 million. One of the leading suspects there allegedly spent much of the money on luxury automobiles including two Lamborghinis, a Ferrari and a Bentley.

Officials did not speculate on how many of those charged might face jail time if convicted.