Suspect VWs in Europe too

Dobrindt told reporters in Berlin on Thursday that he had been "informed" that European cars with 1.6-liter and 2-0-liter diesel engines were among 11 million VW 2009-2015 vehicles suspected worldwide.

In Brussels, European Commission spokeswoman Lucia Caudet said the EU's executive was "inviting" each of the 28 member countries to check on how many vehicles in the national fleet may have used so-called "defeat devices" to pass their emissions tests.

Volkwagen head Martin Winterkorn resigned on Wednesday, saying he personally had done nothing wrong but took responsibility for "irregularities" disclosed by the US Environmental Protection Agency (EPA) last Friday.

The EPA accused VW of installing software in cars sold in the US to make their engines appear to run cleaner during emissions tests than when on the road.

Follow-up tests for other makes

Dobrindt said the exact number of affected vehicles in Europe was unknown, and added that follow-up emissions tests would be extended to other makes.

"We have been informed that also in Europe vehicles with 1.6- and 2.0-liter diesel motors are involved in the manipulation in question," Dobrindt said, adding that the extent would be clarified in the "next few days."

His remarks coincided with a drop of up to 9 percent in BMW share prices on Thursday, amid reports of similar methods to trick the tests. BMW said the report in "Auto-Bild" was incorrect, "and naturally we keep to every country's laws and meet all local test requirements."

Earlier, the German automotive news magazine Auto-Bild had claimed that BMW's X3 xDrive 20d model exceeded "Euro 6" emissions limits more than 11-fold in road tests by the International Council on Clean Transportation (ICCT).

"There is no difference in the treatment of exhaust emissions whether they are on [test] rollers or on the road," said the Munich-based luxury-car maker.

VW US recall in April

In further negative news for VW, California's Air Resources Board confirmed that in April this year Californian owners of certain 2-liter diesel-powered Audis and Volkswagens were sent letters asking them to visit their dealers to obtain a software update for a technical glitch.

The voluntary recall letter said if an indicator became illuminated "for any reason, your vehicle will not pass an IM emissions inspection in some regions."

It said that California required the software update before renewing a vehicle's registration, adding that the software had been "improved to assure your vehicle's tailpipe emissions are optimized."

Environmental group ponders

The German environmental organization NABU on Thursday said it was considering an end to a 15-year cooperation under which VW supported nature conservation projects such as seeking to boost wolf numbers across Europe.

Referring to car manufactures as a whole, NABU said Dobrindt "must instruct the Federal Motor Transport Authority to conduct additional tests on the road to expose further shortcomings and in particular to end them."

"It's been long known that the manufacturers systematically resort to tricks on the fringe of legality," NABU said.

The European Commission has proposed new legislation to tighten vehicle testing in line with real driving conditions.

More resignations at VW?

A member of VW's supervisory board, which includes state and trade union representatives, Olaf Lies, said Thursday he expected more resignations.

Lies, who is economy and transport minister in the VW's northern German home state of Lower-Saxony told Berlin-Brandenburg RBB public radio that the probe was only just starting.

"There must be people responsible for allowing the manipulation of emission levels to happen," he said.

Unconfirmed reports on Thursday, carried by German paper "Bild" and news agency Reuters, suggested that the research and development bosses of Audi and Porsche, Ulrich Hackenburg and Wolfgang Hatz, would resign at VW's board meeting on Friday, along with VW US chief executive Michael Horn.

VW has filed a criminal complaint with German prosecutors, seeking to identify those responsible.

ipj/msh (AP, Reuters, EPD, dpa)