German carmakers, Volkswagen, BMW and Daimler have confirmed research they commissioned into the carcinogenic properties of diesel emissions used caged monkeys to test the fumes health risks.
The German government and all three carmakers have since denounced the study and condemned the use of animals.
The research was carried out by the European Research Group on Environment and Health in the Transport Sector, also known as EUGT, and it is unclear if the carmakers were aware of monkeys being used in the experiments.