Iraqi security forces pull down a flag belonging to Sunni militant group Islamic State of Iraq and the Levant (ISIL) during a patrol in the town of Dalli Abbas in Diyala province, June 30, 2014. The leader of the al Qaeda offshoot now calling itself the Islamic State has called on Muslims worldwide to take up arms and flock to the "caliphate" it has declared on captured Syrian and Iraqi soil. Picture taken June 30, 2014. REUTERS/Stringer (IRAQ - Tags: CIVIL UNREST POLITICS MILITARY TPX IMAGES OF THE DAY) - RTR3WS9J Reuters
Family members and U.S. officials say the Islamic State in Iraq and Syria militant group has been holding a young American woman hostage in Syria since last year.
The woman had been working for several humanitarian aid groups when she was kidnapped by ISIS. A ransom demand of $6.6 million US has been made, ABC News reported.
The U.S. government and the woman's family requested Tuesday that she not be named because of fears for her safety.
The administration officials spoke on condition of anonymity because they were not authorized to discuss the issue publicly.
The woman is one of at least three known hostages of Islamic State militants in Syria. Another, James Foley, was beheaded by the militant group more than a week ago. Other American hostages were being held by other groups. These include Peter Theo Curtis, 45, an American journalist who was released by al-Nusra Front earlier this week.
President Barack Obama said Tuesday "America does not forget," and he vowed justice for the murder of the U.S. journalist.
Speaking in Charlotte, N.C., the president said the country continues to grieve for Foley, calling called his killers "barbaric terrorists." He signalled that a response may take some time.
He said "rooting out a cancer like [ISIS] won't be easy, and it won't be quick." But he said America is patient and "justice will be done."