The NFL's investigation into whether the New England Patriots used deliberately under-inflated footballs against the Indianapolis Colts in the AFC Championship game has focused on a locker room attendant at the Patriots' stadium.

Fox Sports reported Monday that the attendant could be seen on surveillance video bringing 12 balls supplied by the Patriots for use on offense into another room at Gillette Stadium after a pregame inspection by the game officials. Under NFL rules, each team must present their chosen footballs to the game officials for inspection and approval two hours and fifteen minutes before the start of each game.

Fox Sports also reported that the attendant was interviewed by NFL investigators last week as part of their investigation. It has not been determined whether any wrongdoing took place.  

The NFL has said that balls provided by the Patriots for the game against the Colts were underinflated, though it is not clear why. League rules mandate that game balls must be inflated to a minimum of 12.5 pounds per square inch and a maximum of 13.5 pounds per square inch. 

The Patriots defeated the Indianapolis Colts, 45-7 in the AFC title game Jan. 18 to advance to their sixth Super Bowl since 2001. 

NFL Executive Vice President Jeff Pash and Ted Wells of the law firm of Paul Weiss are leading the probe. Wells was the lead investigator into the Miami Dolphins bullying scandal involving offensive linemen Richie Incognito and Jonathan Martin.

Later Monday, Patriots owner Robert Kraft said that he hoped the NFL would apologize to his team if the league's investigation failed to find any wrongdoing. 

The Associated Press contributed to this report.

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