According to Reuters, Nissan's investigation into Renault Chairman and CEO Carlos Ghosn is expanding.
The investigation is looking into alleged misconduct by Ghosn.
They are seeking to determine if Ghosn under reported his compensation and personal use of company assets.
The 64-year-old chairman was recently arrested in Tokyo, along with fellow director Greg Kelly.
But the investigation may also end Nissan's alliance with Renault.