Eleven Championship clubs have complained to the English Football League about Leeds spying on opposition teams, the governing body has announced.
Leeds head coach Marcelo Bielsa has admitted to having all their Championship opponents watched in training this season, having had a member of his staff caught in the act by Derby.
The EFL and Football Association are investigating the matter and the EFL has been approached by many of Leeds' rivals voicing their concerns about events.
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 to watch them train ahead of their Championship game at Elland Road eight days ago, 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 has been magnified by Leeds' position at the top of the 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.
But Bristol City owner Steve Lansdown has publicly voiced his opinion about the matter and wants a points deduction for Leeds.
Speaking to BBC Points West on Friday, he said: "The only thing that makes sense if I'm honest is a points deduction.
"They ought to seriously consider it, but I don't think that will happen as I don't think the EFL will be strong enough to do something like that. A fine would go some way towards showing it's not acceptable. Whatever happens we mustn't condone it.
"If he'd asked to send someone to watch our training we would have said no. And every other football club would say no. So why does he think it's acceptable to do it?
"However great a coach he is, it's the wrong thing to do. Poking around and skulking around a training ground is not part of the game."
Meanwhile, Derby are advertising for a new analyst to improve the team's pre-match preparations.
The vacancy, which appears in the jobs and careers section of the club's official website, was posted prior to the recent spying controversy.
The position is for an "experienced data integration architect" to work as part of Derby's data and football analysis teams.
While the key responsibilities section does not require entering rival training grounds using pliers, which is what Derby boss Frank Lampard claimed the Leeds member of staff did, it does ask for applicants to "think outside of the box" on ideas to improve the club's database and information.
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