Screen legend Marlon Brando, famous for his roles in On the Waterfront and The Godfather, has died aged 80 in a Los Angeles hospital, his lawyer has said.
Marlon Brando starred in classics such as Last Tango in Paris
Brando, who had been ill for some time, was regarded as one of the pivotal actors of the post-war period.
He starred in more than 40 films, including Apocalypse Now, and won two best actor Oscars.
He is perhaps best known for his role as mafia leader Don Corleone in the 1972 classic The Godfather.
Brando's lawyer, David J Seeley, said the cause of death was being withheld and added that the actor "was a very private man".
Mr Seeley said Brando's funeral arrangements would be private.
Tributes have been flooding in.
Karl Malden, who also starred in On the Waterfront, described how theatre productions featuring Brando would have to pause "for a minute and a half" after he gave a speech because of the audience's cheering.
"This is the Marlon Brando I knew," he said.
Italian actress Sophia Loren said, "Actors such as him should be immortal. He was a wonderful work companion, a person of great education, a true professional."
Actor Robert Duvall, who starred with Brando in The Godfather, paid tribute, saying: "His memory will live forever."
Native Americans have also mourned the passing of a high-profile campaigner for their cause.
Brando famously sent a woman in native American garb to collect one of his Oscar awards and to protest at the US' neglect towards the continent's earliest inhabitants.
The BBC's Peter Bowes in Los Angeles commented: "He was a film icon, often described as the greatest actor of his time.
"He was a very, very private character, reclusive even."
Brando received eight Oscar nominations during his lifetime - all for best actor apart from his most recent nod in 1990 for A Dry White Season, which was for best supporting actor.
His two Oscar wins were for On the Waterfront and The Godfather.
The other nominations were for Last Tango in Paris (1973), Sayonara (1957), Julius Caesar (1953), Viva Zapata! (1952) and Streetcar Named Desire (1951).
At the time of his death, he was working with French-Tunisian director, Ridha Behi, on a film following an Arab youth's gradual disenchantment with the American dream.
He was to have played himself in "Brando and Brando" - personifying of all that outsiders admire about America.
He once said: "The only thing an actor owes his public is not to bore them."
His personal life was well documented and marked by tragedy.
The Brando family was in the spotlight at the murder trial of the actor's son Christian, accused of killing the abusive fiance of his sister Cheyenne
Christian later served five years of a 10-year sentence for manslaughter.
Brando's daughter Cheyenne committed suicide in 1995.
He had at least 11 children with three ex-wives and various other women.
In later years, he became increasingly reclusive.
Brando, who had a well documented weight problem, told an interviewer in the 1990s that he had withdrawn under the stress of being constantly in the public eye.
"I've had so much misery in my life, being famous and wealthy," he said.
Alan Yentob will present a tribute to Marlon Brando in a special edition of the BBC arts programme, Imagine, later this month.