Democrat Tim Kaine and Republican Mike Pence faced off in Tuesday's debate over banning immigrants from areas that foster terrorism, with Pence saying the safety of Americans must come first.

Kaine said that GOP presidential nominee Donald Trump's plan for "extreme vetting" of Muslim immigrants amounts to religious discrimination. He also noted that a federal appellate court on Monday upheld an injunction against Pence's action to keep Syrian refugees from settling in Indiana, where he serves as governor.

"The judges said there wasn't any evidence yet that ISIS [the Islamic State terror group] had infiltrated the United States," Pence responded. "Well, Germany just arrested three Syrian refugees."

Pence said Democrat Hillary Clinton and Kaine want to expand the program to bring in Syrian refugees despite fears from Republicans that ISIS members could be embedded among them.