State Dept.: Western passport holders fighting with ISIS is a 'growing threat'

(CNN) – An American named Douglas McCain was killed last weekend in Syria, where he was fighting for ISIS (also known as ISIL), two U.S. officials told CNN.

"Reports like this do raise this issue, which is our concern about the growing threat from ISIL, the growing concern we have about individuals who have Western passports, who are able to gain access whether it's the United States or other allies in western Europe," said State Department spokesperson Jen Psaki.

"That's one of the reasons this is top of our agenda and a topic of discussion internally in the administration right now," Psaki said in an interview with CNN's "The Lead with Jake Tapper."

For more of our interview with the State Department's Jen Psaki, check out the video above.