Pressed on what he'd do to prevent any further attacks, Trump asserted that he would make it "very, very hard for people to come into our country" from "terrorist areas.

When Van Susteren pointed out that these attacks aren't solely initiated by overseas actors, and that homegrown terrorists are also a problem -- pointing to the massacre in Orlando, Florida last month by a U.S. citizen -- Trump pushed back and said that "second generation" immigrants were also "very bad."

"Second generation turns out to be very bad for whatever reason," the candidate said. "But second generation and again, who knows the new one in France? Maybe it's not, but you probably have a pretty good gut instinct."