In issuing its report, the watchdog said that of the $4.9 billion in expected recoveries for this year, $4.1 billion came from investigative work.

The Office of Inspector General of the Department of Health and Human Services said the agency will return $4.9 billion in improperly spent federal healthcare dollars to taxpayers from oversight and probes conducted this year, mostly through fraud investigations that targeted Medicare and Medicaid abuse.

The head of HHS’ Office of the Inspector General, Daniel R. Levinson, informed Congress in the watchdog’s semiannual report that probes revealed $4.1 billion in misspent federal funds and that about $834.7 million was discovered missing via program audits. Levinson said $1.1 billion of the full amount would be allocated to Medicare restitution for states.

According to the report, 533 civil and administrative cases were filed in 2014, with certain false claims and unjust enrichment suits being transferred to federal district court, while others looked at civil monetary penalties through administrative procedures.

The report also highlighted other OIG accomplishments, including its Medicare Fraud Strike Force efforts leading to the filing of charges against 228 individuals or entities, 232 criminal actions and $441 million in investigative receivables.

Additionally, the report showed that whistle-blower lawsuits serve as a frequent source of Medicare and Medicaid recovery for the OIG, underlining the $85 million settlement with Halifax Hospital Medical Center, which allegedly provided physicians with kickbacks for unnecessary referrals that were subsequently billed via Medicare, in violation of the Stark Law.