Pete Buttigieg directly criticized Elizabeth Warren over health care at Tuesday night’s debate, saying that she had not been forthcoming about whether she would raise taxes on the middle class to help finance “Medicare for all.”

Ms. Warren, the Massachusetts senator, was asked if she would raise taxes on the middle class, and she responded by focusing on the costs that middle-class families would face. “I will not sign a bill into law that does not lower costs for middle-class families,” she said.

Mr. Buttigieg, who last month called Ms. Warren “extremely evasive” on the issue, criticized Ms. Warren for not directly answering the question.

“We heard it tonight,” Mr. Buttigieg, the mayor of South Bend, Ind., said. “A yes-or-no question that didn’t get a yes-or-no answer. Look, this is why people here in the Midwest are so frustrated with Washington in general and Capitol Hill in particular. Your signature, senator, is to have a plan for everything — except this.”