Washington (AFP) - The United States has opened a criminal investigation into Volkswagen, which has admitted almost 500,000 of its cars in the US have a clean-air cheating device, a source close to the probe told AFP Tuesday.
The investigation is being led by the US Justice Department's environment and natural resources division, the source said, speaking on condition of anonymity and confirming media reports.
The German automaker is already under investigation by the US Environmental Protection Agency, and could face up to $18 billion in fines related to that inquiry.
The California Air Resources Board is also investigating Volkswagen's violations of emissions standards.
Volkswagen, the world's largest automaker by sales in the first half of this year, has said it is cooperating with the various US investigations.
On Tuesday, Volkswagen admitted that 11 million of its diesel cars worldwide are equipped with devices that can cheat pollution tests.
A hearing over the emissions scandal will be held soon in Congress, two Republican lawmakers in the House of Representatives announced Monday.