Kayla Jean Mueller was an American human rights activist and humanitarian aid worker from Prescott, Arizona. She was taken captive in August 2013 in Aleppo, Syria, after leaving a Doctors Without Borders hospital. Media had long reported that a 26-year-old American aid worker was being held by the Islamic State of Iraq and the Levant without naming her, at her family's request. Her captivity and death were widely reported upon confirmation of her death.