Funnyman Robin Williams has spoken out to assure fans he is alive and well following rumours suggesting he died on a movie set in Austria. 

The Mrs Doubtfire star was the victim of an Internet hoax on Friday when a report appeared online and suggested the actor had fallen to his death while filming a movie in Kitzbuhel, Austria. 

Williams was alerted to the rumors and took to Twitter.com to insist the story is not true and he is busy on his stand-up tour of the U.S. 

In a post on the social networking website he writes, "Despite rumors to the contrary, I will be in Savannah tomorrow night at the Johnny Mercer Theater."