Referee Robert Hoyzer admitted he was paid more than $65,000, from a Croatian-controlled betting ring in Berlin, to fix three games.
The German newspaper Sueddeutsche Zeitung reported that Hoyzer was present when other referees received money and that he heard of players getting paid.
Michael Grunwald, a spokesman for the Berlin prosecutors office, said four people were arrested on Friday in Berlin.
Five games, four lower-division games plus a German Cup game, are under investigation by the German federation.
The country\’s biggest soccer scandal in more than 30 years comes with the World Cup in Germany just a year away.
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