Several players around the league have said the Saints and defensive coordinator Gregg Williams weren't the only ones with such a system. Former Redskins safety Matt Bowen said Williams had a similar bounty scheme when he was in Washington.
Aiello said the league would not comment on other reports. He added that the NFL will look at "any relevant info regarding rules being broken," saying that is "standard procedure."
Lions defensive tackle Ndamukong Suh insisted Sunday his team had no bounty program.
"I don't take part in those things and nor do my teammates and nor my coaches. We don't allow that," said Suh, who was suspended for two games this season for stomping on an opponent and has been fined frequently by the NFL for rough play."
"For me, personally, and I know my teammates, we don't want to put anybody out," he added. "Especially me, I would never want anybody to target me to take me out, so why would I do it against somebody else."
The Saints maintained a bounty pool of up to $50,000 the last three seasons, the NFL said. Payoffs came for inflicting game-ending injuries, among other events. The investigation by NFL security found that quarterbacks Brett Favre and Kurt Warner were among the players targeted. "Knockouts" were worth $1,500 and "cart-offs" $1,000, with payments doubled or tripled for the playoffs.
All payouts for specific performances in a game, including interceptions or causing fumbles, are against NFL rules. The NFL also warns teams against such practices before each season.
The NFL said the findings were corroborated by multiple, independent sources, and the pool amounts peaked in 2009, the year the Saints won the Super Bowl.
"The payments here are particularly troubling because they involved not just payments for 'performance,' but also for injuring opposing players," Commissioner Roger Goodell said Friday in a statement. "The bounty rule promotes two key elements of NFL football: player safety and competitive integrity."
The league said 22 to 27 defensive players were involved in the program and it was administered by Williams, with the knowledge of coach Sean Payton.
"It was a terrible mistake," Williams said. "And we knew it was wrong while we were doing it."
No punishments have been handed out, but they could include suspension, fines and loss of draft picks.
Williams also has been the defensive coordinator in Tennessee and Jacksonville, was the head coach of the Buffalo Bills, and in January was hired by new Rams coach Jeff Fisher to lead the defense.
The league could look into whether such bounties were used with any of those teams and, of course, with the Redskins in light of Bowen's comments.
In New Orleans, players contributed cash to the pool, at times large amounts, and in some cases the money pledged was directed against a specific person, the NFL said.
One Saint fined last season for flagrant hits was safety Roman Harper. In Week 14 against Tennessee, he made two hits that drew a total of $22,500 in fines.
Harper was fined $15,000 for roughing the passer on a helmet-to-helmet hit, and another $7,500 for unnecessary roughness when he pulled down receiver Damian Williams by his helmet after a long catch and run. The tackle likely stopped Williams from scoring, and Gregg Williams defended Harper's aggressiveness on that play after the game.
"If that guy doesn't want his head tore off, duck. Because that's how we're playing. He needs to duck, OK? And that is exactly what you have to do," Williams said. "One of the things about playing in this league is that your mental toughness, your physical toughness, all that kind of stuff works hand in hand. And I love Roman Harper and the way he plays, and evidently a lot of other people and players in the league do, too, because they keep on voting him to the Pro Bowl."
AP Sports Writers Rick Freeman in New York and John Marshall in Phoenix contributed to this story.