Republican presidential front-runner Donald Trump said Sunday that there is a "very severe problem" with some Muslims, and declined to say whether he'd support a Muslim president of the United States. In an interview on NBC's "Meet the Press," Trump said that he feels "strongly that Muslims are excellent. I know so many Muslims that are such fabulous people. But he continued,"We can be politically correct and say there is no problem whatsoever, but the fact is, there is a problem with some and it's a very severe problem and it's a problem that's taking place all over the world.