Proof that the FBI investigation that's rocked college basketball is far from over and essentially guaranteed to lead to more arrests came Wednesday when The Oklahoman obtained a copy of a subpoena a New York grand jury sent to Oklahoma State that demands all documents and communications regarding "actual or potential NCAA rules violations" by people connected to the men's basketball program.

The subpoena demands that Oklahoma State either gather the evidence and turn it over to a New York FBI agent by Oct. 17 or have a university representative travel to New York and appear in person before the grand jury to testify at that time. The grand jury is requesting emails, text messages, cell phone records, social media messages, computer records and many other documents and electronic records covering the time period from Jan. 1, 2014 to present. That time frame covers a span in which the program was led by three different coaches: Travis Ford, Brad Underwood and Mike Boynton. Ford is now the coach at Saint Louis. Underwood is now the coach at Illinois. Boynton has been Oklahoma State's coach since March.

The only person connected to Oklahoma State arrested to date is Lamont Evans, who joined OSU's staff in April 2016. He was arrested Sept. 26 and charged with conspiracy to commit bribery and five other counts related to allegations that he accepted bribes to steer student-athletes to financial advisers. Oklahoma State fired Evans two days later. He's expected to appear in a New York courtroom for the first time Thursday. The three other college basketball coaches arrested Sept. 26 -- Arizona assistant Book Richardson, USC assistant Tony Bland and Auburn assistant Chuck Person -- were in a New York courtroom Tuesday. Each was released on a $100,000 bond after relinquishing his passport.

So far 10 men have been arrested in the three-year FBI investigation that's uncovered various crimes that Joon H. Kim, the acting United States Attorney for the Southern District of New York, described this way last month: "Coaches at some of the nation's top programs [were] taking cash bribes, managers and advisers [were] circling blue-chip prospects like coyotes, and employees of a global sportswear company [were] funneling cash to families of high school recruits." Most famously, the scandal has already led to Louisville placing athletic director Tom Jurich, men's basketball coach Rick Pitino and assistants Kenny Johnson and Jordan Fair on administrative leave.  More arrests are expected, possibly as soon as this month, sources have told CBS Sports.