Rep. Steve King, an Iowa Republican who has retweeted and met with far-right groups with ties to Nazis, defended himself against accusations of being an anti-Semite over the weekend by telling the story of his recent trip to Poland to visit sites of the Holocaust.

The Jewish non-profit group From The Depths, which raises money to take members of Congress and other other public figures to see Holocaust memorial sites, recently hosted King on a five-day tour through Poland.

Stops included Auschwitz, various museums, and Warsaw, the capital city that was completely destroyed during World War II. King and his wife traveled with a concentration camp survivor who is now in his mid-90s and lives in New Jersey.

“To walk through that place and hear from that man all of the things that he experienced and the stories that he knew, to see the grief on his face, to look at that vast expanse in Birkenau of the industrialized slaughter of people that I do not understand why anyone would dislike any of them, is a stunning experience,” King said at a question-and-answer event in Iowa’s 4th District over the weekend.

King has been heavily criticized for an interview he gave on that same trip to members of the far-right Austrian Freedom Party — which was founded by a former Nazi SS officer and is now led by a man who ran in neo-Nazi groups when he was a teenager — where the congressman lamented that “Western civilization is on the decline.”

After a gunman killed 11 people at a synagogue in Pittsburgh in October, King’s past tweets and comments decrying the perceived demise of white Americans as the U.S. becomes more diverse received renewed scrutiny.

National Republicans have not clamored to King’s defense, even as he faces an unexpected challenge from former professional baseball player and Democratic nominee J.D. Scholten in a race that Inside Elections with Nathan L. Gonzales rates Likely Republican.

Instead, National Republican Congressional Committee Chairman Steve Stivers publicly condemned King’s behavior.

“Congressman Steve King’s recent comments, actions, and retweets are completely inappropriate,” Stivers tweeted on Tuesday. “We must stand up against white supremacy and hate in all forms, and I strongly condemn this behavior.”

President Donald Trump carried King’s district by 27 points in 2016.

King led Scholten by just 5 points in a New York Times/Sienna College survey conducted from Oct. 31 through Nov. 4.

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