Academy Awards co-hosts Amy Schumer and Wanda Sykes said on Wednesday that they were sickened by Best Actor winner Will Smith slapping Chris Rock at Sunday night's ceremony.
Meanwhile, the Academy of Motion Picture Arts and Sciences said Smith had been asked to leave, but refused.
He is being given at least 15 days’ notice of a vote about his breaches of the academy's code of conduct and any possible penalties.
Smith will be given the opportunity to be heard beforehand with a written response. The organisation’s board of governors are scheduled to meet again on April 18.
During the live Oscars broadcast, Smith stormed on to the stage after Rock made a joke about his wife, Jada Pinkett Smith, and slapped the comedian in the face.
Rock had referred to the 1997 film GI Jane, in which actress Demi Moore shaved her head. Pinkett Smith suffers from alopecia, although it is unclear if Rock was aware.
“Wow. Wow, Will Smith just smacked the [expletive] out of me,” Rock said.
Smith then stomped back to his seat and yelled obscenities at the presenter.
Rock tried regaining his composure enough to announce the winner of best documentary, Questlove's Summer of Soul.
"Still triggered and traumatised," Schumer said in a post on Instagram three days later.
"I love my friend Chris Rock and believe he handled it like a pro. Stayed up there and gave an Oscar to his friend Questlove and the whole thing was so disturbing.
"So much pain in Will Smith ... I’m still in shock and stunned and sad. Waiting for this sickening feeling to go away from what we all witnessed."
Sykes also called the incident "sickening" and that she felt physically ill at the time.
"I'm still a little traumatised," she said in clips released on Wednesday from an interview on the Ellen DeGeneres talk show.
Less than an hour after his attack on Rock, Smith won Best Actor for his role as the father of tennis legends Venus and Serena Williams in King Richard.
He gave a tear-filled acceptance speech in which he apologised to the academy and his fellow nominees, but not Rock.
Sykes said Smith should have been escorted out and not permitted to accept his award.
"For them to let him stay in that room and enjoy the rest of the show and accept his award, I was like, 'How gross is this? This is just the wrong message'," she said.
The clash with Rock overshadowed the night's awards, in which heart-warming movie Coda won Best Picture. Schumer and Sykes co-hosted the ceremony with Regina Hall.
Smith apologised to Rock and others on Monday, saying he "reacted emotionally" to the joke about Pinkett Smith, who is an actor and talk show host.
If the academy's board concludes that Smith breached its conduct policy, it could expel him from the organisation, revoke his Oscar or make him ineligible for future awards.
Rock has declined to press charges.
Reuters contributed to this report.