The head of Volkswagen Group of America will testify before a House subcommittee Oct. 8.

Volkswagen AG has admitted using a piece of engine software to cheat on diesel car emissions tests in the U.S., where authorities say there are 482,000 such cars. The company says that up to 11 million vehicles worldwide were fitted with the engine in question.

A House Energy and Commerce subcommittee will hear testimony from Volkswagen Group of America President and CEO Michael Horn and also the Environmental Protection Agency.

Lawmakers on the panel sent a letter to Volkswagen’s CEO Tuesday requesting all documents and communications related to compliance with the Clean Air Act and federal emissions standards. Committee leaders also asked the EPA to provide a timeline of the how it discovered VW’s violations.