NASHVILLE, Tenn. (AP) — When federal agents descended on the Knoxville headquarters of Pilot Flying J on April 15, it was the first inkling the public and company executives had of an FBI and Internal Revenue Service investigation that began nearly two years ago.

After the country's largest diesel retailer sought to downplay the scope of fraud allegations, federal officials took the unusual step of unsealing an affidavit before charges were filed. It recounts internal Pilot conversations that led investigators to conclude there was a widespread scheme to defraud trucking company customers in order to boost company profits and pad sales commissions.

Pilot is run by Cleveland Browns owner Jimmy Haslam, the brother of Tennessee Gov. Bill Haslam. There are several Flying J and Pilot truck stops in Idaho including one in the Magic Valley.