The Justice Department announced an expansion of its Northeast Health Care Fraud Strike Force to Philadelphia to investigate alleged Medicare and Medicaid fraud involving home health care services.

Federal and state authorities charged 19 defendants accused of participating in schemes involving more than $4 million in fraudulent claims.

Prosecutors allege some defendants billed for services that were impossible, including care provided while aides were hospitalized, incarcerated, overseas, or working other jobs.

The cases also include allegations of fake time records, false patient claims, and improper billing by home health agencies, Fox News has reported.

The new Philadelphia office will work with agencies including the FBI and the Department of Health and Human Services to strengthen efforts against health care fraud.