The Environmental Protection Agency of the US on Thursday accused Fiat Chrysler of using secret software that allowed illegal excess emissions from at least 104,000 diesel vehicles, a report said.

Affected models include 2014-2016 Jeep Grand Cherokees and Dodge Ram 1500 trucks with 3-liter diesel engines that were sold in the United States, The Boston Globe reported, citing the agency.

The software resulted in excess emissions of nitrogen oxides, which carry harmful health effects, from the vehicles, the agency said.