LEAVENWORTH, Kan. (AP) - A civil rights group says staff at a privately run Leavenworth prison repeatedly have disparaged a Muslim woman for wearing a headscarf and ordered her to take it off before allowing her to leave her cell.

The Kansas City Star reports that the Washington-based Muslim Advocates raised concerns about the treatment of 49-year-old Valeriece Ealom in a letter to CoreCivic, the Tennessee-based company that operates the prison. The letter, which was made public Wednesday, also was sent to the U.S. Marshals Service, which contracts with CoreCivic to house federal prisoners.

Ealom has been held at the facility since last November after federal prosecutors moved to revoke her parole in a drug case. She has sued over her treatment.

CoreCivic did not immediately respond to questions from The Star.