A protester wearing a turban was ejected from a Donald Trump campaign rally Sunday, just as Republican presidential candidate went on a screed against "radical Islamic terror" on stage.

The man was part of a group of protesters that interrupted Trump's rally in Muscatine, Iowa, a regular occurrence at the GOP front-runner's gatherings.

As Trump spoke about the terrorist attacks on September 11, 2001, the demonstrators unfurled a banner that proclaimed "STOP HATE."

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"We have radical Islamic terror going on all over the place, all over the world, and we have a president that won't say it," the GOP front-runner said. "When planes fly into the World Trade Center, and into the Pentagon, and wherever the third plane was going. When people are shooting their friends in California, when they're shooting their friends -- "

Trump stopped his speech as chants from the audience of "Trump! Trump! Trump!" grew.

Addressing the activists, the GOP contender waved his hand, shook his head, and said, "Bye. Bye. Goodbye."

After the disruption quieted down, Trump asked the audience, "He wasn't wearing one of those hats, was he? Was he wearing one of those?"

He then continued his speech: "And he never will. And he never will. And that's OK, but you know we've got to do something folks cause it's not working."

It is unclear whether Trump was referring to the red turban the man was wearing when he commented on "one of those hats," or if the candidate mistook it for one of the red "Make America Great Again" hats often sported by rally attendees.

The campaign did not immediately respond to a request for comment.