To avoid being perceived as radical, organizers rejected support from Communist groups. However, some politicians claimed that the March was Communist-inspired, and the Federal Bureau of Investigation (FBI) produced numerous reports suggesting the same. In the days before August 28, the FBI called celebrity backers to inform them of the organizers' communist connections and advising them to withdraw their support. When William C. Sullivan produced a lengthy report on August 23 suggesting that Communists had failed to appreciably infiltrate the civil rights movement, FBI Director J. Edgar Hoover rejected its contents. Strom Thurmond launched a prominent public attack on the March as Communist, and singled out Rustin in particular as a Communist and a gay man.