German prosecutors have indicted former Volkswagen CEO Martin Winterkorn and four others on charges of fraud and unfair competition, saying he failed to prevent the manipulation of engine software that let Volkswagen cars cheat on diesel emission tests.
Four other executives are also being charged, the prosecutors' office in Brunswick in VW's home of Lower Saxony said in a statement.
USA prosecutors have already filed criminal charges against Winterkorn, accusing him of conspiring to cover up the automaker's diesel-emissions cheating.
VW first admitted in September 2015 that it had used illegal software to cheat U.S. emissions tests.
The automaker apologized and pleaded guilty to criminal charges in the United States, where two executives were sentenced to prison and six others charged, although they could not be extradited.
The Braunschweig prosecutors said people accused of particularly serious fraud could face up to 10 years in prison in Germany. Prosecutors said bonus that could be forfeited ranged from around 300,000 euros to 11 million euros ($340,000 to $12.45 million).
In a statement, prosecutors accused Mr Winterkorn of a "particularly serious" fraud, as well as a breach of competition laws.
Criminal proceedings against the carmaker over the rigged tests had already resulted in a one billion euro fine in June past year, marking one of the highest ever punitive payments imposed by German authorities against a company.
VW has admitted installing software in its diesel cars that turned on pollution controls when vehicles were being tested and switched them off during everyday driving.
The prosecutors' move is only one of the legal proceedings unleashed by the scandal.
Last month the US Securities and Exchange Commission announced it was suing Volkswagen and its former chief executive, accusing them of defrauding investors by making "deceptive" claims about the environmental impact of its cars.
Former engineering executive Oliver Schmidt was imprisoned for seven years in the USA for his part in hiding the software from regulators.
Winterkorn's attorney, Felix Doerr, said that the defence could not comment on the German case because prosecutors had not provided adequate opportunity to review the case files. First, the Braunschweig prosecutors are continuing their probe against 36 more suspects, according to Monday's news release.
A Volkswagen spokesman said the company would not comment on investigations against individuals. Investors in Germany are also seeking damages over VW's failure to disclose the issue.