BERLIN (AFP) - European champions Bayern Munich are again dominating this season but behind the scenes, coach Pep Guardiola has threatened the mole who is leaking details of tactics to the German press.

"No matter who it is, heads will roll. I will throw him out and he'll never play for me again," Guardiola fumed to German daily Bild.

The Spaniard is furious after details of Bayern's tactical plan appeared in Bild, hours before Saturday's 3-0 league win at rivals Borussia Dortmund in a replay of May's Champions League final.

Chairman Karl-Heinz Rummenigge confirmed the "mole affair" to German Sky on Sunday with a tongue-in-cheek reference to America's National Security Agency, which is currently under fire for covertly collecting data on European leaders.

"We won't be turning to the NSA to find out who it is, but I would advise the person concerned to immediately stop this performance," said Rummenigge.

"Otherwise he will have a serious problem, not only with Pep Guardiola, but with the whole club."

Bayern are currently four points clear in the Bundesliga and the holders have already qualified for the Champions League knock-out stages with two games left.

This is not the first time a mole has recently struck in German football.

In June 2012, Germany head coach Joachim Loew was presented with a similar problem when the team's line-up was also leaked to Bild during the European Championship.

But on that occasion, the mole was never revealed.