Donald Trump is keeping the battle of words with Sen. John McCain (R-Ariz.) going, questioning whether McCain should be considered a war hero.

The Associated Press reported that at the Family Leadership Summit in Iowa Saturday, moderator Frank Luntz described McCain as “a war hero.” The senator was a prisoner of war for over five years after his plane was shot down during combat in Vietnam.

Trump gave a comment and gasps could be heard in the crowd.

Trump just now on John McCain: “He's a war hero because he was captured. I like people who weren't captured.”

— Karen Travers (@karentravers) July 18, 2015

Here is the clip of Trump's pathetic comment on John McCain. pic.twitter.com/nGwxriq390

— Austin Barbour (@Austin_Barbour) July 18, 2015

Trump and McCain have been trading comments through the media for the past week. Trump called McCain “very weak” on immigration and said he’d probably lose this election.

McCain fired back with comments in the New Yorker. on Monday.

“It’s very bad,” McCain told the publication. “This performance with our friend out in Phoenix is very hurtful to me. Because what he did was he fired up the crazies.”

McCain referenced McCain’s military career earlier in the week on Twitter.

.@SenJohnMcCain should be defeated in the primaries. Graduated last in his class at Annapolis–dummy!

— Donald J. Trump (@realDonaldTrump) July 16, 2015