Trump melts down: 'How stupid are the people of Iowa?'

Republican candidate Donald Trump went on an extended rant Thursday night, calling Iowa voters "stupid" for supporting Ben Carson and asking how anyone could be so dumb as to believe Carson's "crap."

"How stupid are the people of Iowa? How stupid are the people of the country to believe this crap?" he asked in a speech in Iowa.

Trump also mocked Carson's explanation of how he ended up not stabbing someone as a child because the blade was turned away by his belt buckle.

"So I have a belt: Somebody hits me with a belt, it's going in because the belt moves this way," Trump said as he moved his belt around.