A Pentagon investigation found a $50 million contract to promote the Thunderbirds aerial stunt team was tainted by improper influence and preferential treatment, leading to administrative action against three officials, the Air Force said Thursday.

Air Force Secretary Michael Wynne took administrative action against Maj. Gen. Stephen M. Goldfein, who was the commander responsible for the Thunderbirds at the time, as well as two others, and referred action on two additional personnel to their commanders, according to a release issued by the service. Wynne also ordered a review of contracting processes and a training program to correct problems raised by the investigation.

The Air Force said the IG probe found that the contract was "tainted with improper influence, irregular contracting practices and preferential treatment for SMS." The release also said the assistant U.S. Attorney in Nevada has declined to pursue any criminal prosecution.

"I am deeply disappointed that our high standards were not adhered to in this case," Wynne said in a statement. "This is not how the Air Force does business and we are taking steps to ensure this doesn't happen again."