Will Smith apologized to Serena and Venus Williams after slapping Chris Rock at the Oscars

• Will Smith stole the headlines at the Oscars when he slapped Chris Rock.
• He's now apologized to the comedian, as well as Serena, Venus, and the rest of the Williams family.

Will Smith has apologized to tennis stars Serena and Venus Williams after slapping Chris Rock at the Oscars on Sunday.

Smith, who won best actor the Best Actor award on the night for his portrayal of the Williams sisters' dad in the biopic "King Richard," stormed the stage and attacked Rock after the comedian made a joke about his wife, Jada Pinkett Smith, while presenting an award.

Rock had made a joke about Pinkett Smith's shaved head, a result of the hair-loss condition alopecia.

"Violence in all of its forms is poisonous and destructive," said Smith in an apology shared on his social media platforms.

"My behaviour at last night's Academy Awards was unacceptable and inexcusable. Jokes at my expense are a part of the job, but a joke about Jada's medical condition was too much for me to bear and I reacted emotionally.

"I would like to publicly apologize to you, Chris. I was out of line and I was wrong."

Smith went on to say sorry to Serena, Venus, and the rest of the Williams family for tarnishing the night.

"I would like to apologize to the Williams family and my King Richard family. I deeply regret that my behaviour has stained what has been an otherwise gorgeous journey for all of us. I am a work in progress," he said.

Both Serena and Venus were at the Sunday's awards ceremony at the Dolby Theatre in Los Angeles.

After Smith slapped Rock, Serena took to Instagram to react, sharing a video of herself with her mouth agape in shock. In a second video, she said that she had to "sit down" and put her drink down as a result of the drama.

On Tuesday, Serena appeared to respond to the incident once again, posting a brief video on her Instagram story showing her seemingly on a private jet while saying: "And that is a wrap. I am so ready to go home."

The Academy of Motion Pictures Arts and Sciences said Monday it was opening a formal investigation into Smith's attack on Rock, saying it would "explore further action and consequences in accordance with our Bylaws, Standards of Conduct, and California law."