The war of words between Republican presidential candidate Donald Trump and Sen. John McCain has just been kicked up a notch.

"He's not a war hero," Trump said at the 4th annual Family Leadership Summit in Iowa today. "He's a war hero 'cause he was captured. I like people that weren't captured."

Other GOP candidates didn't appreciate Trump's strong words, and they immediately took to Twitter to defend McCain and his service.

Perry released the following statement in response to Trump’s comments:

“Donald Trump should apologize immediately for attacking Senator McCain and all veterans who have protected and served our country. As a veteran and an American, I respect Sen. McCain because he volunteered to serve his country. I cannot say the same of Mr. Trump. His comments have reached a new low in American politics. His attack on veterans make him unfit to be Commander-in-Chief of the U.S. Armed Forces, and he should immediately withdraw from the race for President.”

Watch Mike Emanuel's full report from the Family Leadership Summit in the clip above.

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