Robin Williams dead at 63: Tributes pour in from President Barack Obama, Steven Spielberg and Steve Martin

Reuters: Oscar-winning actor and comedian Robin Williams was found dead at age 63 on Monday from an apparent suicide at his home in Northern California, authorities said.

Hollywood celebrities and many others who knew him paid tribute to Williams:

His wife Susan Schneider said in a statement: "This morning, I lost my husband and my best friend, while the world lost one of its most beloved artists and beautiful human beings. I am utterly heartbroken."

President Barack Obama, in a statement making reference to the actor's many roles said: "Robin Williams was an airman, a doctor, a genie, a nanny, a president, a professor, a bangarang Peter Pan and everything in between. But he was one of a kind. ... The Obama family offers our condolences to Robin's family, his friends and everyone who found their voice and their verse thanks to Robin Williams."

Director Steven Spielberg said in a statement: "Robin was a lightning storm of comic genius and our laughter was the thunder that sustained him. He was a pal, and I can't believe he's gone."

Officials from Twentieth Century Fox Television, the studio that produced Williams's show "The Crazy Ones," said in a statement: "Robin Williams was a comedy giant, and although we only knew him personally for a season, he was warm, funny and a true professional."

Actor Steve Martin said on Twitter: "I could not be more stunned by the loss of Robin Williams, mensch, great talent, acting partner, genuine soul."

Actor John Cryer said on Twitter: "We will try to carry on, but it won't be any fun without you."

Musician John Mayer said on Twitter: "The first thing I ever wanted to be when I grew up was Robin Williams' inhabiting of Popeye."

Actor Neil Patrick Harris said on Twitter: "I am stunned and just reeling from the news of Robin Williams' death. He brought so much joy and heart to millions ... Just, wow."

Actress Minnie Driver said on Twitter: "My Heart's broken. Robin was a beautiful, kind soul. Can't bear that he's gone. So incredibly sorry for his family."

Comedian Margaret Cho said on Twitter: "I AM BEYOND DEVASTATED."

Comedian Jimmy Kimmel said on Twitter: "Robin was as sweet a man as he was funny. If you're sad, please tell someone."