The NFL is investigating whether the Las Vegas Raiders violated locker room access protocol during their Monday night game against the New Orleans Saints, according to ESPN’s Adam Schefter.

The NFL’s strict COVID-19 protocols limit the non-players and coaches who can enter the locker room. Per league rules, only 40 employees (aside from players) are allowed access to the locker room.

Those employees are the team’s coaching staff, training personnel, equipment staff, general manager, a security person and a communications person.

According to the report, league officials believe a non-credentialed team employee entered the Raiders’ locker room on Monday night.

The league has fined coaches and teams $1.75 million so far this season for failing to comply with mask requirements aimed at stopping the spread of the coronavirus.

Raiders coach Jon Gruden was fined $100,000 and the team was fined $250,000 for violating the mask policy in Week 2.

On Friday, the league sent a memo reminding teams of the rules ahead of Week 3.

“All individuals, except for active players in the bench area, are required to wear face coverings at all times on game day, including on the sidelines and in the coaches’ booth,” said the memo, shared by NFL Network’s Tom Pelissero via social media.

The memo reiterated that the rule applies to all non-playing club personnel and “strongly encouraged” players who don’t expect to substitute into the game to wear masks.

The NFL also fined Pete Carroll (Seattle Seahawks), Kyle Shanahan (San Francisco 49ers), Vic Fangio (Denver Broncos) and Sean Payton (New Orleans Saints) and their teams for violating the mask policy in Week 2.