NEW YORK (CBSNewYork/AP) — Clay Matthews, Julius Peppers and James Harrison will be interviewed next month by NFL officials in connection to a media report that linked them to the use of performance-enhancing drugs.

A letter from NFL executive Adolpho Birch that was obtained by The Associated Press says Green Bay linebackers Matthews and Peppers and Pittsburgh linebacker Harrison will be interviewed when training camps open. The Packers begin practicing July 26, the Steelers on July 29.

The letter also mentions defensive lineman Mike Neal, a free agent who will be interviewed. It doesn’t mention the now-retired Peyton Manning, who also was cited in Al-Jazeera’s report in December.

The NFL first notified Matthews, Peppers, Harrison and Neal about its investigation into the report on Jan. 11. That investigation has proceeded, but Birch wrote that the players’ union hasn’t responded to “multiple requests” to schedule the interviews.

The Al-Jazeera report was based secret recordings of a former intern at an Indianapolis anti-aging clinic, who later said he fabricated the entire story.

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