Fiat Chrysler has been accused of not telling authorities about software that regulates emissions in thousands of its diesel vehicles. The US Environmental Protection Agency said the company broke the law by installing, but failing to disclose, the technology in more than 100,000 Jeeps and Dodge vehicles. The agency said the software caused higher nitrogen oxide levels. Fiat Chrysler boss Sergio Marchionne said the firm had done nothing illegal. “There was never any intent of creating conditions that were designed to defeat the testing process. This is absolute nonsense,” he added. Shares in Fiat Chrysler ended the day 10.3% lower in New York and closed 16% lower in Milan. The EPA said Fiat Chrysler could be liable for fines of about $44,500 per vehicle, which would mean a total of about $4.6bn.