Will Smith's mother says she was surprised by the Oscars slap: 'That's the first time I've ever seen him go off'

• Carolyn Smith said she was surprised when Will Smith slapped Chris Rock at the Oscars.
• "That's the first time I've ever seen him go off," Carolyn said.

Carolyn Smith, Will Smith's mother, spoke to local media in her hometown of Philadelphia about the moment her son slapped Chris Rock onstage during the Oscars on Sunday.

"He is a very even, people person. That's the first time I've ever seen him go off," Carolyn told Action News about the moment Will slapped Rock. "First time in his lifetime. I've never seen him do that."

Caroline — who still resides in Philadelphia — continued to say that the now-famous slap did not dampen the family's celebrations as Will Smith picked up the best actor award later during the Oscars ceremony.

"I am proud of him being him," Carolyn said. "I know how he works, how hard he works ... I've been waiting and waiting and waiting. When I heard the name, I was just, 'Yes!'"

Earlier this morning, Will Smith posted an apology to Chris Rock on Instagram for slapping the comedian at the Academy Awards after he made a joke about his wife, Jada Pinkett Smith, during an onstage monologue.

In the joke, Rock made reference to Jada Pinkett Smith's bald head. Pinkett Smith has alopecia, a hair-loss condition, and has been open about struggling with it."Can't wait for 'G.I. Jane 2,'" Rock said. In the 1997 movie "G.I. Jane," star Demi Moore shaves her head bald.

"Violence in all of its forms is poisonous and destructive. My behavior at last night's Academy Awards was unacceptable and inexcusable," Smith said in the Instagram post.

"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."

Smith went on to say sorry to Serena, Venus, and the rest of the Williams family for the incident. Smith won the best actor Oscar for his performance in "King Richard," a biopic about the life of the two tennis stars.

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

A post shared by Will Smith (@willsmith)

Both Serena and Venus were at Sunday's awards ceremony at the Dolby Theatre in Los Angeles. After hitting Rock, Will Smith walked back to his chair, sat next to his wife, and yelled back to Rock: "Keep my wife's name out of your fucking mouth!"

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