US actor James Caan, who rose to fame for his portrayal of Sonny Corleone in The Godfather, has died aged 82.

A leading man in Hollywood throughout the 1970s whose career spanned decades; he was nominated for an Oscar, an Emmy and four Golden Globes.

Caan's family thanked fans on Thursday for an "outpouring of love and heartfelt condolences".

The New Yorker, known for his partying lifestyle, was married four times and leaves behind five children.

Among the tributes to Caan, fellow actor Gary Sinise wrote on Twitter that it had been "wonderful to know him and call him a pal", while filmmaker Rob Reiner said he "loved working with him".

Comedian Andy Richter said he had been "lucky enough, after a lifetime of loving [Caan's] work, to get to work with him and I loved him as a person even more... They say never meet your heroes, but he proved that to be very very wrong".

Born to a butcher in the Bronx, Caan initially planned on pursuing a career as an American Football player.

He took to acting when he began studying at Hofstra University, where he met Francis Ford Coppola - his director in The Godfather.

After a string of minor TV and film appearances, Caan finally got his big break in 1965, when he starred in two Howard Hawks films: Red Line 7000 and El Dorado.

But it was 1972's mob drama epic The Godfather that saw him become a household name.

He had originally auditioned for the role of Michael Corleone, and was reportedly favoured for the role by studio executives.

But after Coppola's insistence, Al Pacino was chosen for that role.

Caan played Michael's older brother Sonny, and was fitted with more than 140 explosive blood pellets to simulate gunshot wounds for the character's death scene.

The role saw him receive his only Academy Award nomination for best supporting actor.

Caan briefly disappeared from public view in the early 1980s during what he has described as "a pretty scary period" brought on by drug use and his sister's death.

But he engineered a comeback with memorable roles in hit movies like Elf and Misery.

His tough-guy persona would also be tempered by appearances in more light-hearted films, including 2009 animation Cloudy with a Chance of Meatballs.

Beyond his Hollywood endeavours, Caan also trained in karate for some three decades.

In his later years, he would become prolific on Twitter, building a large following and often capping his posts with the phrase "End of tweet".

The final post on his account reads: "It is with great sadness that we inform you of the passing of Jimmy on the evening of July 6... End of tweet."