SALT LAKE CITY — A former FBI agent pleaded guilty Monday to charges that he derailed an investigation into military contract fraud by making a suspect appear to be a key counterintelligence source.

Retired agent Robert Lustyik Jr. pleaded guilty to 11 federal charges of fraud, conspiracy and obstruction of justice charges, said Lustyik’s attorney, Raymond Mansolillo. Lustyik’s trial was scheduled to start Monday in federal court, but Mansolillo said his client pleaded guilty for personal and family reasons.

Lustyik, 52, wouldn’t accept a plea deal because he didn’t want to implicate anyone else, Mansolillo said. Federal prosecutors say Lustyik agreed to derail a Utah-based investigation into a company started by former soldiers. The company was accused of using insider information to win $54 million in bloated government contracts to supply Afghan troops.