Hundreds of fans had queued to see the reformed group
Reunited boy band New Kids on the Block have performed together for the first time in 15 years.
Hundreds of fans watched the group sing a medley of their hits, including Right Stuff and Hangin' Tough, at the Rockefeller Plaza in New York.
Joey McIntyre said: "I think the story is the fans more than anything and that's what makes us feel so good."
The band also sang their new single Summertime during their performance for TV network NBC's Today programme.
Some fans had been waiting for 48 hours so they were able to get the best view of the group - brothers Jordan and Jonathan Knight, Donnie Wahlberg, Danny Wood and McIntyre - on stage.
Karen Alexander, 29, travelled from Virginia to see them.
"It was absolutely amazing. New Kids are back. The singing, the dancing, they are going to take over the world," she said.
Radio 1 Newsbeat's Sima Kotecha, who was there, said: "You could hardly hear yourself speak because the screaming was so loud.
New Kids on the Block will tour North America in September
"The atmosphere was buzzing and it was surprising to see so many people out even though it was cold and raining."
Wahlberg was the one who suggested the group get back together, but he told the crowd he did not want to "take credit for it".
He said: "If we weren't getting along, if we couldn't record in the studio together and honestly if the fans didn't want it, it may not have happened.
"We found a great record, we recorded it and the brotherhood was still there."
Wood compared the experience of reuniting like "riding a bike".
The group are releasing Summertime ahead of a North American tour which starts in September.