“No, no, you’re not man enough, you’re not man enough,” he said. “I’ll break you in half. Like a boy.”

Initially, Mr. Grimm sought to justify his behavior and did not apologize.

“I was extremely annoyed because I was doing NY1 a favor by rushing to do their interview first in lieu of several other requests,” he wrote in a statement on Tuesday night. “The reporter knew that I was in a hurry and was only there to comment on the State of the Union, but insisted on taking a disrespectful and cheap shot at the end of the interview, because I did not have time to speak off-topic.”

“I verbally took the reporter to task and told him off, because I expect a certain level of professionalism and respect, especially when I go out of my way to do that reporter a favor,” he wrote. “I doubt that I am the first member of Congress to tell off a reporter, and I am sure I won’t be the last.”

But on Wednesday, Mr. Grimm seemed to have had a change of heart. “I was wrong,” he said in a statement. “I shouldn’t have allowed my emotions to get the better of me and lose my cool. I have apologized to Michael Scotto, which he graciously accepted, and will be scheduling a lunch soon.”

Mr. Grimm’s actions were quickly picked up by the national media, and Mr. Scotto appeared on several cable networks on Wednesday morning to talk about what had happened.

“I don’t believe the substance of the threat at all,” he said on CNN. “I’m not taking it personal. I just think he was angry by the fact that I asked that question and I think he was even more angry by the fact that I kind of explained to viewers why he was not going to answer that question.”

Mayor Bill de Blasio, joining a chorus of critics, said Mr. Grimm’s actions were “absolutely inappropriate'’ and called on the House to sanction him.