(Reuters) - The U.S. Justice Department said on Friday that former Volkswagen Chief Executive Martin Winterkorn, indicted on four felony charges in Detroit in the company’s diesel emissions scandal, is a fugitive who faces a U.S. arrest warrant.

Former Volkswagen chief executive Martin Winterkorn leaves after testifying to a German parliamentary committee on the carmaker's emissions scandal in Berlin, Germany, January 19, 2017. REUTERS/Hannibal Hanschke

As long as Winterkorn remains in Germany, the U.S. warrant is unlikely to have practical impact because Germany does not extradite its citizens to the United States.

Winterkorn, 70, a German citizen, was indicted in March on fraud and conspiracy charges, but the case was only unsealed on Thursday.

David Ashenfelter, a spokesman for the U.S. District Court in Detroit, confirmed a warrant for Winterkorn’s arrest was issued.

Nicole Navas Oxman, a Justice Department spokeswoman, said on Friday, “Martin Winterkorn remains a fugitive.” A Volkswagen spokeswoman declined to comment, except to reiterate that the company is still cooperating.

“We are surprised at the charge,” a lawyer for Winterkorn, Felix Doerr, told German news outlet Handelsblatt.

A grand jury in Detroit has indicted nine people in connection with the diesel emissions scandal. Two former VW executives have pleaded guilty and been sentenced prison terms, while a former manager of VW’s Audi unit, Giovanni Pamio, 61, an Italian citizen, has been charged and remains in Germany pending extradition.

The remaining six, including Winterkorn, are believed to be in Germany and are unlikely to face U.S. charges. Prosecutors in Germany are also investigating the VW emissions issue.

The September 2015 disclosure that VW intentionally cheated on emissions tests for at least six years using secret software led to Winterkorn’s ouster, damaged the company’s reputation around the world and prompted massive bills.

In total, VW has agreed to spend more than $25 billion in the United States to address claims from owners, environmental regulators, states and dealers and offered to buy back about 500,000 polluting U.S. vehicles.