BERLIN (AP) — The software at the center of Volkswagen's emissions scandal in the U.S. was built into the automaker's cars in Europe as well, though it isn't yet clear if it helped cheat tests as it did in the U.S., Germany said Thursday.

A day after longtime CEO Martin Winterkorn stepped down, a member of Volkswagen's supervisory board said that he expects further resignations at the automaker in the wake of the scandal.

The U.S. Environmental Protection Agency disclosed Friday that stealth software makes VW's 2009-2015 model cars powered by 2.0-liter diesel engines run cleaner during emissions tests than in actual driving.

The EPA accused VW of installing the so-called "defeat device" in 482,000 cars sold in the United States. VW later acknowledged that similar software exists in 11 million diesel cars worldwide and set aside 6.5 billion euros ($7.2 billion) to cover the costs of the scandal.

The company has told officials that the vehicles in question included cars with 1.6-liter and 2-liter diesel engines in Europe, German Transport Minister Alexander Dobrindt said Thursday.

"We don't yet have figures for how many of these 11 million cars that are apparently affected are in Europe," Dobrindt said. "That will be cleared up in the next few days."

Authorities will continue working with Volkswagen to determine what cars exactly are involved.

It isn't yet clear to what extent the scandal affects other brands in the Volkswagen Group, which has 12 brands in all — including Seat, Audi, Skoda and Porsche. It was also not clear whether the software would have led to VW cheating on emissions tests outside the U.S. as well.

Dobrindt this week set up a commission of inquiry to look into the scandal. The motor transport authority is conducting static and road tests on Volkswagen models and spot tests on cars made by other manufacturers, German and foreign.

Also Thursday, Olaf Lies, economy and transport minister of VW's home state Lower Saxony, which holds a 20 percent stake in the company, said the investigation into the scandal was only just starting.

"There must be people responsible for allowing the manipulation of emission levels to happen," he told rbb-Inforadio.

Winterkorn said Wednesday he took responsibility for the "irregularities" found by U.S. inspectors in VW's diesel engines, but insisted he had personally done nothing wrong.

VW is filing a criminal complaint with German prosecutors, seeking to identify those responsible for any illegal actions in connection with the scandal.

Other auto companies have seen the Volkswagen scandal weigh down their shares.

On Thursday, shares in BMW dropped 5.2 percent to 75.62 euros ($83.13) after Germany's Auto Bild magazine reported that road tests by the International Council on Clean Transportation showed the BMW X3 xdrive model exceeding European emissions limits by more than 11 times. It did not say what the cause for the alleged problem was.

BMW said in a statement that it was not familiar with the test and would ask the ICCT for clarification. It said that "the BMW Group does not manipulate or rig any emissions tests."