Zohran Mamdani officially took the oath of office as the clock struck midnight on New Year's Eve, becoming the 112th mayor of New York City. In a private ceremony at the abandoned Old City Hall subway station, Mamdani was sworn in by New York Attorney General Letitia James. The 34-year-old democratic socialist, who served in the 36th Assembly District representing the Queens neighborhood of Astoria, is now the city's first Muslim mayor and its first of South Asian descent. | CBS News

As Big Ben chimed midnight, London rang in the New Year with fireworks over the River Thames. https://abcnews.visitlink.me/7Txs_3 | ABC News

Epic performances. Iconic moments. Midnight magic! Chappell Roan, Post Malone, Charlie Puth, Demi Lovato and more are here for the party you can’t miss! Join host Ryan Seacrest for Dick Clark’s New Year’s Rockin’ Eve, TONIGHT at 8/7c on ABC! 🎉 🎶 | ABC

Zohran Mamdani was officially sworn in as New York City's 112th mayor just after midnight Thursday during a private ceremony, but a public ceremony and celebration are planned for later this afternoon. You can stream it live on CBSNewYork.com or the CBS News app. | CBS New York