Complex sentence: OCR is one of the largest federal civil rights agencies in the United States, with a staff of approximately 650 attorneys, investigators, and staff located in twelve regional offices and in Washington, D.C., headquarters.
Split into simpler sentences: OCR is one of the largest federal civil rights agencies in the United States, with a staff of approximately 650 attorneys, investigators, and staff. The agency is located in twelve regional offices and in Washington, D.C., headquarters.