The New England Patriots are denying new reports of spying, this time on the opponents they'll face this Sunday. The Cincinnati Bengals reportedly think the Patriots tried stealing signs after a Patriots production crew was caught filming the Bengals' sideline during their game Sunday against the Cleveland Browns.

The Patriots, who were punished in 2007 for taping opponents, said the crew was there to film for a documentary series. The NFL is investigating to determine whether it was something more.

As the Cleveland Browns claimed victory over the Cincinnati Bengals Sunday, suspicions brewed in the press box above. A Bengals official said he saw a Patriots employee inappropriately filming the sidelines during the game, and notified the NFL.

"I'm aware that there was an incident but I know the league is investigating it, so I have no comment," Cincinnati Bengals head coach Zac Taylor said.

The Patriots, who lead the AFC East with 10 wins, said they were filming a Patriots scout at the game for an upcoming episode of their behind-the-scenes web series "Do Your Job." In a statement Monday, the team said it got the Browns' permission to shoot, but not the Bengals' or the NFL's.

Coach Bill Belichick denied having any knowledge of the filming during a conference call on Tuesday. "I have no involvement in this and no knowledge of it, and so I really don't have any idea what exactly is going on," he said. "I can tell you that we've never, as a coaching staff and me, personally, have never viewed any video footage at all of anything that those production people have done, other than what's shown on public television or something like that."

Tom Brady talks with Bill Belichick at Gillette Stadium on November 24, 2019, in Foxborough, Massachusetts. Adam Glanzman / Getty

In 2007, the Patriots were fined $250,000 after an investigation found they spied on the New York Jets' coaches during a game. Then in 2016, quarterback Tom Brady was suspended for four games over an accusation that he was involved in deflating footballs during the 2015 AFC championship game to make them easier to grip.

"I didn't alter the ball in any way," Brady said at the time. "I've always played within the rules. I would never do anything to break the rules."

The NFL has confiscated the tape as part of its investigation and declined to comment on the matter.

Vladimir Duthiers contributed to this report.