New York, New Jersey and the U.S. have entered into a $15.5 million settlement agreement with a radiology practice serving Long Island, N.Y., after allegations that the practice submitted false claims to Medicaid and Medicare for services that weren’t ordered and weren’t medically necessary.

Doshi Diagnostic Imaging Services, the radiology practice, and Diagnostic Imaging Group, which provides management and support services for the practice, will return nearly $3 million to the New York State Medicaid program, while more than $12 million will be returned to the federal Medicare program. Additionally, the state of New Jersey will recover $190,000, according to the New York State Office of the Attorney General.

From 1999 to 2010, the companies were alleged to have submitted false billings for thousands of services, including retroperitoneal ultrasounds, Doppler scans, transrectal ultrasounds and pelvic x-rays.

The settlement also resolves allegations that the companies were involved in an illegal kickback scheme in which physicians were paid more than fair market value for supervision of nuclear stress tests from Oct. 5, 2001, to July 22, 2012.

The investigation stemmed from three whistleblower lawsuits brought by individuals in 2009 and 2010.