The NFL Players Association has warned its members about the possibility of a financial scam, Sporting News has learned.

After receiving inquires from current players over the past two weeks, the NFLPA issued a security alert Friday about three tax advisory firms operated or controlled by a Chicago-area resident named John Richard Burgess.

The NFLPA said one player was assessed a fee of $500,000 for services from one of those entities.

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The NFLPA also detailed a history of criminal charges and fraud claims against Burgess dating back to 1988, as well as a lengthy list of other active businesses to which he is connected.

No claims of illegality were made by the NFLPA against Burgess in a memo that was circulated to all current and former union members for what was listed as “informational purposes." However, that doesn't discount the possibility of legal action against Burgess by players in the future.

The NFLPA works to warn members about being exploited by financial advisors and the like, which remains an ongoing problem despite efforts by the union and NFL to better educate players about protecting their earnings.

Burgess, 67, is listed as residing in North Barrington, Ill.