French investigators will probe Renault over suspected "cheating" in emissions tests of diesel motors, the Paris prosecutors office said Friday, causing shares in the automaker to fall sharply.Following a massive emissions scandal involving Germany's Volkswagen, independent French experts found dangerously high levels of emissions from diesel engines of several carmakers, including Renault.Prosecutors have ordered a probe be opened into "cheating on key parts (of vehicles)" and into the quality of the tests carried out. The probe comes after another global auto maker, Fiat Chrysler, fell foul of US environmental standards on Thursday.The company was charged with having hidden software on diesel trucks which then spewed out excess emissions. The US Justice Department also charged six Volkswagen executives deemed responsible for the conspiracy, five of whom are believed to be in Germany while one was arrested in Miami on Saturday.