Toyota supplier Denso Corp. says the FBI and Department of Justice have raided its U.S. headquarters as part of an antitrust investigation.

Denso spokeswoman Julie Kerr says the supplier's office, located in Southfield, Mich., was raided on Tuesday. She says the company is cooperating with the investigation, but declined to offer details of what the government was looking for.

Kerr says the investigation is unrelated to Toyota's recent recalls. Denso is a major parts supplier for Toyota and is one of two suppliers of its gas pedals. While gas pedals from the other supplier were involved in Toyota's sticky accelerator recall, Denso's have not been implicated.