Iowa Rep. Rod Blum's Monday sit-down interview with a local television station was going well, until he got a question he didn’t like.

The Republican was in his hometown of Dubuque chatting with TV9 investigative reporter Josh Scheinblum ahead of a town hall at a local high school gymnasium.

There was about a minute of cordial conversation about the congressman’s town hall tour, until Scheinblum asked why Blum required attendees to show their IDs.

Blum explained he wanted to ensure only people from his district attended. He doesn’t represent all Iowans, he said, just those in his northeast district.

“That’d be like saying, ‘Shouldn’t I be able to, even though I live in Dubuque, go vote in Iowa City during the election?’” the congressman argued.

Scheinblum then asked: “Would you still take donations from a Republican in Iowa City?”

Blum, surrounded by school children, stood up, took off his microphone, and said, "This is ridiculous. This is ridiculous. He's going to sit here and just badger me."

He walked out, setting the tone for a feisty town hall. Later, the Washington Post reported, Blum said Scheinblum ambushed him.

“It was very apparent that he had an agenda,” he said. “It’s my right to say that this interview is over.”

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The Post reports two of Blum’s top contributors during his 2016 re-election efforts were from out of state.

At the event, the about 1,000 attendees were checked in by volunteers, who were accompanied by police officers, the Post reported. TV9 noted Blum did not permit hand-written signs, so people held up red papers for when they disagreed and green for when they agreed.

Many asked about Blum's vote last week to repeal the Affordable Care Act. Blum, the Post reported, said the change affects about 12,000 people in his district and for most people nothing will change. The statement was followed by boos and shouts.

Blum later tweeted thanks to the group for a "great discussion."