Internal memos and emails from Volkswagen suggest the German automaker mislead U.S. regulators in regards to its diesel emissions scandal in 2014.

According to The New York Times, German newspaper Bild am Sonntag reported internal Volkswagen documents suggest that the automaker was confronted in early 2014 with evidence that its diesel vehicles were emitting far more pollutants than legally allowed. They also indicate that the company’s executives knew about the diesel emissions scandal before it openly admitted to it last September.

It is believed that top managers were aware that Volkswagen’s diesel vehicles weren’t compliant with air-quality rules, but led federal and California officials to believe otherwise.

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The report also adds that a confidant of Martin Winterkorn, Volkswagen’s CEO at the time, warned Winterkorn in May 2014 that regulators might accuse Volkswagen of using a defeat device on its vehicles. Volkswagen did not admit publicly that it cheated on EPA diesel emissions tests until September 2015, after which Winterkorn resigned on September 23. At the time, Winterkorn claimed that he did not learn about the defeat device until shortly before Volkswagen’s announcement.

The documents could result in even more penalties for Volkswagen, based on laws requiring public disclosure of problems that have the potential to affect a company’s stock price. Earlier, it was reported that Volkswagen has been reluctant to hand over internal documents to U.S. investigators, citing German privacy laws as an excuse to not provide emails or other communications among its executives.

This article originally appeared at AutoGuide.com