Volkswagen’s (VOW3) troubles are far from over. Washington lawmakers are swiftly getting involved, grilling Volkswagen’s U.S. CEO Michael Horn in a hearing under oath on Thursday. The testimony was held before the House Committee on Energy and Commerce Subcommittee on Oversight and Investigations. The company and its executives are under fire following the automaker's unprecedented emissions scandal involving 11 million vehicles. Volkswagen admitted using devices to sidestep fuel efficiency tests in various diesel vehicles. 'I did not think that something like this was possible at the Volkswagen Group,’ Horn told lawmakers. ‘We have broken the trust of our customers, dealerships, and employees, as well as the public and regulators.' Horn said the company ‘takes full responsibility’ for its actions and is ‘working with all relevant authorities in a cooperative way.’ Horn also acknowledged the consequences that lie ahead for the automaker, which could include up to an $18 billion fine from the EPA. TheStreet’s Scott Gamm reports from New York.