Eleven Championship clubs have complained to the EFL about Leeds spying on opposition teams, the governing body has confirmed.
Leeds head coach Marcelo Bielsa has admitted to spying on other Sky Bet Championship teams, having had a member of his staff caught in the act by Derby last week.
The English Football League (EFL) and Football Association are investigating the matter and the EFL has been approached by many of Leeds' rivals voicing their concerns about the matter.
An EFL Spokesman said: "The EFL has received a communication on behalf of a number of Championship Clubs in regard to the current matter involving Leeds United.
"The request attributed to 11 Clubs will be considered as part of the current investigation that has commenced."
The "spygate" scandal, as it has been dubbed, involved Bielsa sending a member of his staff down to the Derby training ground last week to watch them train ahead of their Championship game at Elland Road, which Leeds won 2-0.
While Leeds do not appear to have actually broken any rules, Bielsa's actions have upset many clubs. The situation is perhaps magnified by the fact that Leeds are currently top of the Championship table.
Bielsa called a hastily-arranged media briefing on Wednesday to present his in-depth analysis to journalists in the hope of showing that his research is so thorough that he gained no advantage from watching Derby train.
In the press conference the Argentinian admitted to having every one of their Championship opponents watched in training this season.
Click the image below to see what managers, including Pep Guardiola, Mauricio Pochettino and Jurgen Klopp have had to say about spygate...
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