Nicole Kidman was left open mouthed as Will Smith slapped comedian and presenter Chris Rock during the live Oscars ceremony.
The 54-year-old Aussie actress was seated in the star-studded audience and appeared visibly shocked and her stunned reaction appears to be echoed by a global TV audience who watched the unprecedented event unfold in disbelief.
Smith stormed on stage during the Sunday night award ceremony and preceded to slap Chris Rock following an off-color joke about his wife Jada Pinkett Smith's hair loss, which is due to alopecia.
Hollywood stars quickly took to Twitter to react to Smith's outburst, with comedian and director Judd Apatow calling the display 'pure out of control rage and violence' and claiming that Smith 'could have killed' Rock.
''Seems like Will Smith's plan to get comedian and the world to not make jokes about him is not going to pan out. The Williams family must be furious. Pure narcissism,'' he wrote.
Apatow strongly rejected a Twitter user who said they 'understood' why Smith hit Rock because of Jada Pinkett Smith's alopecia.
In a now deleted post he penned: ''He could have killed him. That's pure out of control rage and violence. They've heard a million jokes about them in the last three decades. They are not freshman in the world of Hollywood and comedy. He lost his mind,'' he wrote.
Smith, 57, who was nominated and later won Best Actor for his performance in King Richard, was triggered by reference to his wife preparing to star in a sequel to G.I. Jane, a reference to her bald head.
''Keep my wife’s name out of your f***ing mouth,'' Smith shouted from the audience after returning to his seat near the stage.
American actress and comedian Kathy Griffin agreed with Apatow and called out Smith and said it could open the flood gates for a worrying acceptability of comedian assaults.
Taking to Twitter she penned: ''Let me tell you something, it's a very bad practice to walk up on stage and physically assault a Comedian.
"Now we all have to worry about who wants to be the next Will Smith in comedy clubs and theatres.''
Rob Reiner also condemned Smith saying there was 'no excuse' for what he did and called the apparent justifications in his acceptance speech 'bulls***.'
''Will Smith owes Chris Rock a huge apology. There is no excuse for what he did. He's lucky Chris is not filing assault charges. The excuses he made tonight were bulls***.''
Serena Williams, who plays her father in his latest release King Richard, appeared to react to the behaviour as she shared a brief clip with her mouth hanging open and her eyes wide in shock, on her Instagram.
Smith was forced to make an awkward acceptance speech after winning Best Actor for the movie in which he broke down in tears as he apologised to the Academy.
“I want to be a vessel for love. I want to apologise to the Academy, I want to apologise to all my fellow nominees.
“Art imitates life, I look like the crazy father just like they said about Richard Williams. But love will make you do crazy things.”
But actress Maria Shriver didn't buy Smith's apology.
''#WillSmith says he wants to be a vessel for love. Love is not violent. Love is not what was displayed on a global stage tonight,' she tweeted.
''We should never get to a place where we sit and watch a movie start hit someone on global television.''
Meanwhile The Academy didn't address Smith's behaviour directly but alluded to it in a Twitter post which reads: ''The Academy does not condone violence of any form.''
