NEW YORK (CBSNewYork/AP) — CIA Director John Brennan is warning that the Islamic State of Iraq and Syria wants to conduct Istanbul-style attacks in the United States.

Suicide attackers with guns and bombs killed 41 and wounded hundreds at Istanbul’s Ataturk Airport on Tuesday.

“I am worried from the standpoint of an intelligence professional who looks at the capabilities of Daesh … and their determination to kill as many as people as possible and to carry out attacks abroad,” Brennan told Yahoo News. Daesh is an acronym for the Arabic name of ISIS.

Brennan explained to Yahoo News that he believes the terror group will continue to try to penetrate American defenses.

“You look at what happened in the Turkish airport, these were suicide vests. It’s not that difficult to actually construct and fabricate a suicide vest … so if you have a determined enemy and individuals who are not concerned about escape, that they are going into it with a sense that they are going to die, that really does complicate your strategy in terms of preventing attacks,” the CIA director said.

“I’d be surprised if Daesh is not trying to carry out that kind of attack in the United States,” Brennan added.

Brennan stated that the U.S. hasn’t been able to tamp down ISIS’ global reach.

“We’ve yet to really thwart Daesh’s ability to reach beyond the Syria-Iraqi borders and put in place some of the plans and preparations to carry out attacks,” Brennan told Yahoo News. “I am very concerned we have not had the success against Daesh in that environment as we’ve had in the core areas of Syria and Iraq.”

Brennan also said the terror group is “more determined” to carry out operations in Europe and beyond to “offset” setbacks and losses of territory in Syria and Iraq.

“Over the past year-and-a-half they have made a more determined effort to carry out attacks abroad, and we see in terms of their plans, their preparations, the movement of people as well as propagandizing outside, exhorting, inciting a much more determined effort to carry out these external operations,” Brennan told Yahoo News.

ISIS has yet to confirm they were behind the attack, but Turkish and U.S. officials believe the group planned the suicide bombings at the Istanbul airport.

ISIS has claimed to have “covert units” in Turkey, among other places, according to the SITE Intelligence Group. However, the group rarely claims any attacks in Turkey.

This year alone, a Jan. 12 attack that Turkish authorities blamed on ISIS claimed the lives of a dozen German tourists visiting Istanbul’s historic sites. On March 19, a suicide bombing rocked Istanbul’s main pedestrian street, killing five people, including the bomber, whom the authorities identified as a Turkish national linked to ISIS.

Last October, twin suicide bombings hit a peace rally outside Ankara’s train station, killing 103 people. There was no claim of responsibility but Turkish authorities blamed it on an ISIS cell.