Mr. Mamdani roundly defeated Andrew M. Cuomo in the Democratic contest, widening his primary-night lead by a significant margin once ranked-choice tabulations were run.

President Donald Trump suggested he would order authorities to arrest New York City Democratic mayoral nominee Zohran Mamdani if he doesn’t allow Immigration and Customs Enforcement to operate in the city as mayor.

Zohran Mamdani clinched victory Tuesday in the Democratic primary for New York City mayor and quickly drew more attacks and threats of arrest from President Donald Trump, a Queens native likely to be a central figure in one of this year’s most important contests.