WASHINGTON — An Islamic State detainee currently in U.S. custody at a temporary detention facility in Erbil, Iraq, is a specialist in chemical weapons whom U.S. military officials are questioning about the militant Sunni group's plans to use the banned substances in Iraq and Syria, Defense Department officials said.
Defense Department officials said the detainee, described by the military as a "significant" Islamic State operative who was captured a month ago by commandos in an elite American Special Operations force, has, under interrogation, provided his captors with details about how the group had weaponized mustard gas into powdered form and loaded it into artillery shells.
One Defense Department official said that it was not concentrated enough to kill anyone, but that it could maim people.
As is protocol, Defense Department officials notified the International Committee of the Red Cross, which monitors the treatment of detainees, that they were holding an Islamic State fighter. The Red Cross acknowledged in a statement on Tuesday that it had visited the detainee but gave no other information.
Defense Department officials insist that the United States has no plans to hold the detainee or any other captives indefinitely, and that they will be handed over to the Iraqi and Kurdish authorities after they have been interviewed. The officials say they do not intend to establish a long-term U.S. facility to hold Islamic State detainees, and Obama administration officials have ruled out sending any to the United States military prison at Guantánamo Bay, Cuba.
The chemical weapons specialist was captured last month, shortly after the arrival in Iraq of a new Special Operations force that is made up primarily of Delta Force commandos. They are the first major U.S. combat force on the ground there since the United States pulled out of the country at the end of 2011.
Before this, the U.S. military has largely fought the Islamic State, also known as ISIS or ISIL, with airstrikes, killing large numbers of Islamic State fighters in Iraq and Syria. But the 200-member Special Operations team has been given the task of killing and capturing Islamic State operatives, the latter in particular to use in gathering intelligence.
Defense officials said the team had set up safe houses and worked with Iraqi and Kurdish forces to establish informant networks and conduct raids on Islamic State leaders and other important militants.