Photo

In a tussle outside Trump Tower on Thursday, a member of Donald J. Trump’s security team responded to a protester, who had grabbed him from behind, by hitting him in the face.

The member of Mr. Trump’s security team had ripped a large blue sign reading “Trump: Make America Racist Again” away from protesters gathered outside Trump Plaza, where the candidate signed a pledge to the Republican Party that he wouldn’t stage a third-party candidacy were he to lose the party’s presidential nomination. The protester, identified by NY1 as Efraín Galicia, chased and grabbed the security guard. The guard then turned and swung. As Mr. Galicia was restrained, the security guard disappeared into Trump Tower with the sign.

After the altercation, which occurred under the gaze of multiple television and phone cameras, Mr. Galicia compared his treatment to that of the Univision reporter Jorge Ramos, who was escorted out of a news conference last week by a guard who looked like the man who was involved in the altercation Thursday. Mr. Trump had ejected Mr. Ramos for asking questions without being called on before eventually inviting Mr. Ramos back in.

The Trump campaign said that the security team member on Thursday was “jumped from behind” and that the campaign would “likely be pressing charges.” It did not say whether the security team member was the same man who walked Mr. Ramos out.