Central Intelligence Agency director John Brennan says that the Islamic State could be on the path to acquiring chemical weapons.

"There are reports that ISIS has access to chemical precursors and munitions that they can use," Brennan said Sunday on "60 Minutes."

"We have a number of instances where ISIL has used chemical munitions on the battlefield," Brennan continued.

"60 Minutes" further reported, "The CIA believes that ISIS has the ability to manufacture small quantities of chlorine and mustard gas."

The use of chemical weapons is internationally prohibited.

Brennan continued that the Islamic State would likely continue to attempt to land strikes in the United States.

"I think ISIL does eventually want to find its mark here," Brennan said. "I'm expecting them to try to put in place the operatives, the material, whatever else that they need to do, in order to incite people to carry out these attacks."

"But clearly, I believe that their attempts are inevitable, I don't necessarily think their successes are," Brennan said.