(SportsNetwork.com) - Surveillance video shows a New England Patriots locker room attendant moving game footballs from the officials' locker room into another room at Gillette Stadium before bringing them out to the field for the AFC Championship Game, according to a report.

The NFL has been investigating whether or not the Patriots used underinflated footballs in the AFC title game against Indianapolis. New England won the game 45-7 to earn a berth in this week's Super Bowl against Seattle.

According to FoxSports.com on Monday, the NFL has already interviewed the locker room attendant and is trying to determine if the individual has done anything wrong.

Patriots coach Bill Belichick said during an impromptu news conference on Saturday that he's confident the Patriots did everything by the letter of the law.

Belichick and New England quarterback Tom Brady both denied last week any knowledge of deflated balls being used during the Jan. 18 game, which was played in the rain at the Patriots' home stadium.

ESPN.com reported last week that the NFL found 11 of the 12 balls used by the Patriots were deflated. The league announced that it's early findings suggest the Patriots used underinflated balls in the first half before they were replaced by properly inflated balls, which were used in the second half and retained their air pressure.

The ESPN.com report said the NFL found that 11 of the 12 balls used by the Patriots during the game were underinflated by two pounds of air pressure per square inch (PSI).

NFL rules mandate game balls, which are inspected by the referee hours before kickoff, be inflated between 12 1/2 to 13 1/2 PSI.

Underinflated balls are said to help a player better grip the ball in inclement weather.

The league said Friday the investigation is being led jointly by NFL executive vice president Jeff Pash and Ted Wells of the law firm of Paul Weiss. Wells was the league's investigator into last season's bullying scandal involving the Miami Dolphins.

If the NFL finds the Patriots deflated footballs intentionally, they could be subject to penalties similar to ones levied after the team was found to have videotaped defensive signals used by the New York Jets during a game in September 2007.

Those penalties included a $500,000 fine for Belichick, a $250,000 fine for the team and the loss of a draft pick.