KNOXVILLE (AP) — Four former employees accused in a diesel fuel rebate scam at the nation's largest truck stop chain have struck a plea deal and agreed to cooperate with federal authorities.

Pilot Flying J is run by Jimmy Haslam, owner of the Cleveland Browns and brother of Tennessee Gov. Bill Haslam, who also has a stake in the company. Both have said they had no knowledge of the scheme, which led to criminal charges against executives at the company and an $85 million settlement with some of the defrauded customers as well as a $92 million penalty to the government.

The company said in a statement that it was "saddened" by the news that former employees admitted participating in the scheme. Company officials said they have "made whole every customer negatively affected" and taken steps to make sure this never happens again.

"It is Pilot Flying J's commitment to be a great partner to trucking companies across North America, always focusing our undivided attention on the best interests of our customers, team members and business."

Ten former employees previously pleaded guilty. After the plea agreements filed Monday, four others remain to be tried.

John "Stick" Freeman, the former vice president of sales who was dubbed in court documents as the architect of the scheme, is among those reaching an agreement.

The plea agreements in U.S. District Court also are signed by former regional sales manager John Spiewak, former direct sales group supervisor Vicki Borden and former sales representative Katy Bibee.

Trial is set Oct. 31 in Chattanooga for former Pilot President Mark Hazelwood, former vice president Scott "Scooter" Wombold and two other former members of the sales team, Heather Jones and Karen Mann, the Knoxville News-Sentinel reported.