PROVIDENCE, R.I. — A former Navy subcontractor who was a middleman in a kickback scheme that cost the U.S. Navy $18 million has been sentenced to three years in prison.

Russell Spencer was also ordered to pay $18 million in restitution during sentencing Thursday in U.S. District Court in Providence.

Spencer is one of six people to plead guilty. He pleaded guilty to conspiring to commit bribery and lying to the FBI. Spencer apologized for his actions at sentencing.

The 59-year-old Spencer has acknowledged funneling kickbacks from a Georgia-based Navy contractor to civilian Navy employee Ralph Mariano and others.

The company's founder was sentenced to three years in prison Wednesday. Mariano, who worked for the Naval Undersea Warfare Center in Newport and at the Washington Navy Yard, is serving a 10-year prison term.