Robin Williams has been found dead at his home in California.
The 63 year old comedian best known for his roles in Mrs Doubtfire and Good Morning Vietnam and is believed to have taken his own life.
He had been battling with depression for many years.
The White House has issued a statement paying tribute to the comic.
Barack Obama said he 'gave his immeasurable talent freely and generously to those who needed it most'.
Reporter Greg Milam is in the US - he has details of a statement from Robin Williams' wife:
Robin Williams' daughter Zelda has tweeted a quote from Antoine de Saint-Exupéry, author of The Little Prince
You - you alone will have the stars as no one else has them...In one of the stars I shall be living. In one of them I shall be laughing. And so it will be as if all the stars were laughing, when you look at the sky at night...You - only you - will have stars that can laugh.
I love you, I miss you, I will try to keep looking up. Z
Robin Williams and his wife Susan Schneider whom he married in 2011
Twitter has been flooded with tributes to the late star:
Eddie Izzard @eddieizzard Robin Williams has died and I am very sad. From every comedian here at the Edinburgh Fringe Festival, we salute him and we say goodbye
Jonathan Ross @wossy 5m Robin Williams is gone. I loved him. Incredibly talented performer. Wonderfully sweet and generous person. Heartbreaking news. So sad.
@lindsaylohan Mr. Williams visited me the first day of filming The Parent Trap. I will never forget his kindness. What an enormous loss. My condolences.
@TheEllenShow I can't believe the news about Robin Williams. He gave so much to so many people. I'm heartbroken.
@J0HNNYDepp The world lost a legend of an actor and an extraordinary man today.
Rest In Peace Robin Williams.
@cher He was Sweet LOVELY,Man. He ran high voltage,Mind Always Going, It was who he was.I Know Well..Many X's from High There is Only Low.So Sad??
@johncusack RIP mr Williams - beyond great talent -such a kind and lovely person
