Hillary Clinton said she wasn’t surprised to hear that Donald Trump had used a vulgarity to refer to her this week, but she doesn’t plan to rise to his bait by responding directly to his insults.

“I really deplore the tone of his campaign, the inflammatory rhetoric that he is using to divide people, and his going after groups of people with hateful, incendiary rhetoric,” the Democratic front-runner for president said in an interview with The Des Moines Register after a campaign event in Fairfield. “Nothing really surprises me anymore. I don’t know that he has any boundaries at all. His bigotry, his bluster, his bullying have become his campaign. And he has to keep sort of upping the stakes and going even further.”

Trump, who is a leading Republican candidate, stirred controversy Monday by saying Clinton “got schlonged” in the 2008 election by then-U.S. Sen. Barack Obama. The term is a form of a Yiddish word meaning penis. Trump also told a Michigan rally of his fans it was “too disgusting” that Clinton used the bathroom during a break in Saturday’s Democratic presidential debate.