NEW YORK -- The NFL reminded its players Friday that they are prohibited from taking part in any form of illegal gambling and betting on league games.

In a memo obtained by The Associated Press, the league asked all 32 teams Friday to reiterate key aspects of its gambling policy and make the document readily available to players.

"We all have a responsibility to protect the integrity of the Shield by ensuring that our game is played fairly, honestly and to the best of a player's ability," the NFL management council wrote in the memo. "NFL players must also take appropriate steps to safeguard the game against gambling-related risks that may undermine the confidence and trust of the fans."

The reminder followed an FBI investigation into illicit gambling activities resulted in the arrests of NBA coach Chauncey Billups of the Portland Trail Blazers, Miami Heat guard Terry Rozier and others.

"These developments underscore the risks that all sports are facing in the current environment and serve as a reminder of the need to adhere strictly to the NFL gambling policy," the NFL wrote.

-- throw or fix any NFL game or event, or otherwise manipulate or attempt to manipulate any play or other aspect of an NFL game;

-- share confidential, non-public information regarding any NFL game, player or event with any third party.

"That topic comes up every year," Denver Broncos coach Sean Payton said. "There's a certain amount of presentations. It hits heavy. ... Obviously, it hits the sports world and someone that's a close friend of many of us, myself included, and you hate it. So, obviously, none of it's worth it. ... We've got to be pretty diligent on that."

The NFL Players Association sent a similar memo to players Friday pointing out that they should not bet on the NFL, gamble at the team facility or while traveling for a road game or staying at a team hotel, have someone bet for them, share "inside information," enter a sportsbook during the NFL playing season except to access another part of the casino, or promote any form or gambling or any gambling entity.

NFL players are allowed to legally place bets on other sports as long as they are off club property or not traveling with the team. They also are allowed to take part in traditional fantasy football leagues (prize money cannot exceed $250) and legally gamble at casinos on personal time.

NFL reminds players of league gambling policy in light of federal indictments