NEW YORK -- Jay-Z's electrifying reunion with Alicia Keys on what appeared to be a live duet of "Empire State of Mind" at the Tony Awards was actually pre-taped, a show official who wasn't authorized to speak publicly told The Associated Press.

The appearance of the rapper in support of Keys' musical "Hell's Kitchen" led to a boost of excitement inside the arena but it now appears it was a piece of Hollywood trickery, undercutting the Broadway communities' full-throated embrace of live singing and dancing.

A representative from Jay-Z's Roc Nation and a producer at White Cherry Entertainment did not return messages seeking clarification on what happened Sunday night. A senior publicist for the telecast also did not return requests for comment on Monday.

"Hell's Kitchen," which won two awards Sunday night -- for star Maleah Joi Moon and Kecia Lewis, who plays her mentor -- is loosely based on Keys' years growing up in that Manhattan neighbourhood and contains old hits and new songs from the singer-songwriter. Keys is a producer but doesn't appear in the show. The show ends with a rousing edition of "Empire State of Mind."

Each best new musical nominee at the Tony Awards gets a slot performing and "Hell's Kitchen" was first, with the cast playing a medley of songs -- including her hit "Fallin"' -- from the show.

Then Keys appeared at the piano on the stage of the David H. Koch Theater in Lincoln Center and began singing her and Jay-Z's 2009 smash. She soon got up and went down the steps of the stage and into the orchestra seat section and out the side of the auditorium -- "Had to do something crazy. It's my hometown," she explained to the crowd -- moments later apparently joining the rapper on some of the venue's marble steps to wild applause. "Brooklyn, New York City in the Tonys tonight!" Jay-Z signed-off at the end.

The audience and media was inside the auditorium and no photos have surfaced of the two performers live. A version of the two finishing the song was beamed to the TV audience and a video screen inside the venue. Keys wore the same outfit she was wearing onstage. Jay-Z was never spotted entering the packed auditorium.

While some parts of the Tony telecast are pre-taped -- technical awards handed out before the show, some advertising packages and often segments from the top nominated plays -- the strong feeling is that the musical performances are what audiences will see when they come to Broadway, with no trickery.

New York Magazine first reported that the segment had been pre-taped.