Investigators have said that the University of Texas Southwestern Medical Center and Parkland Memorial Hospital in Dallas may have committed Medicare and Medicaid fraud.

The Dallas Morning News reported on Sunday that a federal investigation has already found millions of dollars in false billings to the government programs for the elderly, disabled and poor.

The newspaper also said that investigators are looking at whether UT Southwestern, one of the country's leading medical schools, billed the government for services faculty physicians did not actually perform while working at Parkland, UT Southwestern's main teaching hospital.

It was also reported that at question is whether physicians billed Medicare for services actually provided by doctors in training, known as residents, supposedly under their supervision.

In February, an internal UT Southwestern internal audit found "systemic failure" in its compliance with billing laws and said the medical center lacked controls to prevent fraud.

The Morning News also said that Medicare and Medicaid are major sources of funding for both UT Southwestern and Parkland. (With Inputs from Agencies)