BMW premises in Germany and Austria have been searched by German state prosectors, investigating defect devices capable of manipulating exhaust emissions.
Around 100 law enforcement officials searched the automaker’s Munich headquarters along with research facilities and a factory in Austria.
Prosecutors said they had opened an investigation last month against unknown persons for suspected fraud.
“There is an early suspicion that BMW has used a test bench-related defeat device,” prosecutors said in a statement.
BMW have long denied its cars are equipped with software designed to manipulate emissions tests, BMW said the findings did not reveal a “targeted manipulation” of emissions cleaning.
The automaker said prosecutors were looking into “erroneously allocated” software in about 11,400 vehicles of the BMW 750d and BMW M550d models.
BMW last month recalled 11,700 cars to fix engine management software, saying it discovered that the wrong programming had been installed.