Volkswagen’s CEO Herbert Diess, chairman Hans Dieter Poetsch, and former CEO Martin Winterkorn are being hit with criminal charges for allegedly waiting to tell investors about the automaker’s rampant emissions cheating, German prosecutors announced on Tuesday. The company’s supervisory board has reportedly called an emergency meeting to discuss the market manipulation charges. Volkswagen and Winterkorn are already being sued by the US Securities and Exchange Commission over similar civil charges.

The charges come almost four years to the day after the Environmental Protection Agency accused Volkswagen (and many of its sub-brands, like Audi and Porsche) of selling diesel vehicles that polluted far more than regulations allowed, a scandal that’s since become known as Dieselgate.

The massive German automaker had masked this fact by installing software on the cars that recognized when they were being put through emissions testing. During these tests, the cars would restrict their emissions enough to comply with regulations. But when they were back on the road, they polluted nitrogen oxide at up to 40 times more than the allowed levels. It was ultimately discovered that 11 million vehicles were affected around the world.

The prosecutors say the three men manipulated the market by not fessing up sooner

Winterkorn was Volkswagen’s CEO when the scandal broke, and Poetsch was chairman, but Diess had only just joined the automaker in July 2015. Still, prosecutors allege the three held a meeting that month about when and how to disclose the emissions cheating to US regulators. News of the scandal didn’t break until September when the EPA and California’s Air Resources Board unveiled the results of their investigation.

Volkswagen has been hit with a number of fines and settlements totaling more than $30 billion since the scandal broke, and multiple executives and employees have been charged, arrested, or forced out of their positions. Volkswagen has spent billions more in an effort to become the leader in electric vehicles, and it recently rolled out two cornerstones of that effort: the ultra-high-end Porsche Taycan, and the mass-market VW ID.3.

The European Union has also accused Volkswagen of colluding with the two other major German automakers, Daimler and BMW, to slow the rollout of better emissions control technology.