African-American coming-of-age tale "Moonlight" won the Oscar for best picture on Sunday on a big night for Hollywood diversity that was overshadowed by an embarrassing onstage gaffe over the top award, Reuters reports.
In a mishap that caused uproar and confusion, presenters Warren Beatty and Faye Dunaway initially announced that romantic musical "La La Land", the presumed favorite for best picture, had won.
As the casts of both films stood awkwardly on stage, Beatty explained he had been given the wrong envelope to open.
It was the first time in living memory that such a major mistake had been made at the Academy Awards, Hollywood's biggest night. It even eclipsed the prior three hours of a show peppered with jokes about U.S. President Donald Trump.
Accountants Price Waterhouse Cooper, who oversee the ballots, said the presenters had mistakenly been given the wrong category envelope.
"We are currently investigating how this could have happened, and deeply regret that this occurred,"
PwC said in a statement, while apologizing to "Moonlight" and "La La Land", Beatty and Dunaway and Oscar viewers.
Officials from the Academy of Motion Picture Arts and Sciences were not immediately available to comment.
"Is that the craziest Oscar moment of all time?" Stone, who won the best actress Oscar for her "La La Land" role as a struggling actress, told reporters backstage "It's a very strange happening for Oscar history."
"Moonlight," about a young boy struggling with poverty and his sexuality in Miami, also brought a supporting actor Oscar for first timer Mahershala Ali, a best adapted screenplay statuette.
Viola Davis won for her supporting role as a long suffering housewife in African-American family drama "Fences."
The recognition for both the actors and their films made a stark contrast to the 2016 Academy Awards when no actors of color were even nominated.
"Moonlight" producer Adele Romanski said she hoped the movie would inspire "little black boys and brown girls and other folks watching at home who feel marginalized."
"La La Land" went into the Oscars with a leading 14 nominations and emerged with six, including for its score and theme song "City of Stars." "La La Land" director Damien Chazelle, 32, became the youngest person to ever win a best director Oscar.
Elsewhere, "Manchester by the Sea" star Casey Affleck was named best actor, winning his first Oscar despite 2010 sexual harassment allegations that resurfaced during awards season. Affleck denied the allegations which were settled out of court.