The Kill Bill star's naked body was discovered hanging in a Bangkok, Thailand, hotel suite. Local reports suggested he committed suicide, but a statement from Carradine's representative indicates the actor died when a sex act went wrong.
Rumors that Carradine died attempting autoerotic asphyxiation -- where victims achieve heightened sexual pleasure by restricting their air supply -- are backed up by a quote a Bangkok police officer gave to British newspaper The Sun.
Stars from the big screen have offered their fond memories of the actor, who had a career spanning back to the 1960s.
The pair had a close relationship after starring together in the two movies and regularly kept in touch between projects.
Madsen reveals he was planning to contact the actor just last week -- and will forever regret not picking up the phone.
He says, "David was one of the first actors I ever worked with when I started my career and the closest person to a brother that I ever had in my life. It is shocking to me that he is no longer with us.
"I had been thinking about calling him for the last several days and advise anybody who has been thinking about reaching out to a loved one to do so. I have so many great memories of David that I wouldn't even know where to begin. He has a very special place in my heart."
Director Scorsese, who worked with the late actor on 1972 movie Boxcar Bertha, recalls Carradine being a "wonderful spirit" who dedicated his life to making movies.
He says, "I was deeply saddened by the news of David Carradine's passing. We met when we made Boxcar Bertha together, almost 40 years ago. I have very fond memories of our time together on that picture and on Mean Streets, where he agreed to do a brief cameo. David was a great collaborator, a uniquely talented actor and a wonderful spirit. He loved movies, acting in movies, making movies and he was always extremely generous."
And the producers of what was to be Carradine's next project are also mourning the loss of the "irreplaceable" star.
Adrian Salpeter and Elizabeth Levine, executive producers of indie film Portland, released a joint statement saying, "An actor of David Carradine's stature behind our film meant the world to us. Our thoughts are with his family and friends at this difficult time.
"The team is committed to this film and are considering other actors to replace the irreplaceable David Carradine. The producers and all involved are moving forward with the production in his memory. Mr. Carradine was truly a living legend of stage and screen, having worked with Martin Scorsese, Hal Ashby, Ingmar Bergman and Quentin Tarantino, among many others, in a career that spanned nearly five decades."
The film's writer/director Matthew Mishory adds, "Every filmmaker aspires to work with an iconic actor like David Carradine. He was one of a kind."
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