FOXBOROUGH, Mass. -- The NFL's investigation into the New England Patriots' underinflated footballs began Sunday night immediately after the AFC Championship Game, has included nearly 40 interviews to this point and is ongoing, the league announced in a statement Friday.
The investigation is being led by NFL executive vice president Jeff Pash and attorney Ted Wells, who previously conducted the league's probe into the Miami Dolphins' bullying scandal. In addition, the league has retained Renaissance Associates, an investigatory firm with sophisticated forensics expertise to assist in reviewing electronic and video information.
The league said in its statement that the Patriots "promptly pledged their full cooperation and have made their personnel and other information available to us upon request."
In a statement, Patriots owner Robert Kraft said over the past three days the team has "provided access to every full- and part-time employee the league's representatives requested to speak with and produced every communication device that they requested to search."
A source confirmed to ESPN.com's Dan Graziano on Friday afternoon that no players have yet been interviewed. Patriots quarterback Tom Brady said late Thursday that he had not talked to NFL investigators.
"While the evidence thus far supports the conclusion that footballs that were underinflated were used by the Patriots in the first half, the footballs were properly inflated for the second half and confirmed at the conclusion of the game to have remained properly inflated," the NFL's statement read.
"The goals of the investigation will be to determine the explanation for why footballs used in the game were not in compliance with the playing rules and specifically whether any noncompliance was the result of deliberate action. We have not made any judgments on these points and will not do so until we have concluded our investigation and considered all of the relevant evidence."
The investigation centers on Playing Rule 2, Section 1, which requires that the balls be inflated to between 12.5 and 13.5 pounds per square inch.
"Prior to the game, the game officials inspect the footballs to be used by each team and confirm that this standard is satisfied, which was done before last Sunday's game," the NFL's statement read.
"The playing rules are intended to protect the fairness and integrity of our games. We take seriously claims that those rules have been violated and will fully investigate this matter without compromise or delay. The investigation is ongoing, will be thorough and objective, and is being pursued expeditiously. In the coming days, we expect to conduct numerous additional interviews, examine video and other forensic evidence, as well as relevant physical evidence.
"Our investigation will seek information from any and all relevant sources, and we expect full cooperation from other clubs as well. As we develop more information and are in a position to reach conclusions, we will share them publicly."
The circus surrounding Deflategate has grown to such a level that even the White House has weighed in. A day after Brady's somewhat awkward news conference, White House press secretary Josh Earnest got a jab in on the Patriots star.
"For years it has been clear that there is no risk that I would take Tom Brady's job as quarterback of the New England Patriots," Earnest said. "But I can tell you that, as of today, it is pretty clear that there is no risk of him taking my job, either."