The spokesman for the Islamic State group, whose rapid offensive in Iraq has triggered U.S. airstrikes, was designated as a terrorist on Monday by the State Department.

The department also applied the designation to Syria-based Algerian national Said Arif, who in 2013 fled house arrest in France in a stolen car and joined the al-Qaida linked group Nusra Front in Syria.

Abu Mohammed al-Adnani, born Taha Sobhi Falaha in Syria, is the official spokesman for and a senior leader of the Islamic State of Iraq and the Levant. The Sunni radical group is trying to expand its hold in northern Iraq, driving back Kurdish forces, sending minority communities fleeing and unleashing a wave of violence over a territory straddling the Syria-Iraq border.

The decision to launch airstrikes marked the first direct U.S. military intervention in Iraq since the last American troops withdrew in 2011 and reflects growing international concern about the extremist group.

The State Department said Arif is wanted by the French government and Interpol. He is an Algerian army officer deserter, who traveled to Afghanistan in the 1990s to do weapons and explosives training in al-Qaida camps. Arif was a suspect in al-Qaida's December 2000 plot to bomb a Christmas market in Strasbourg, France.

In 2003, Arif was arrested and tried in France with 25 others as part of the "Chechen Network."  In 2002, the Chechen Network was accused of plotting to blow up the Eiffel Tower and conduct chemical attacks and attacks on malls and police stations in France.  In 2006, Arif was convicted and sentenced for his role in these planned attacks.  After his arrest, Arif publicly declared that al-Qaida was planning a chemical weapons attack on an American military base in Spain.

The State Department's action prohibits Americans from doing business with either of the two and freezes all property they have within U.S. jurisdiction. Both recently were added to the United Nations' terrorist list, requiring all member states to impose an assets freeze, travel ban and arms embargo against the two.