The star of more than 60 films was having a drink with friends in a bar in Valletta, Malta, during a break in the filming of Stephen Spielberg's new production, The Gladiator, when he became ill. He died on the way to nearby St Luke's Hospital.
A Malta police spokesman said there would be an autopsy later today but there was not thought to be anything suspicious about his death.
Reed was said to be in the bar with his wife, some Maltese friends and crew members of the Royal Navy frigate HMS Cumberland, which is currently in Valletta harbour.
A friend of the actor, who did not want to be named, said: "He had been drinking on the floor when he felt sick. I tried giving him artificial respiration on a bench as an ambulance was called."
Reed, 61, was renowned for his outrageous behaviour and admitted that he loved to shock. It was this urge to be the centre of attention that landed him in so much trouble. Tales abound of his drunken behaviour and violent brawls.
But in an interview in 1995, Reed admitted that he played up to his image because people expected him to put on an act. "Even if I wanted to make myself seem like a normal human being I couldn't, because that's not what people want me to be," he said. "They want a baddy or a carouser or a rake.
"I have cultivated the image of a baddy, which is what I will pursue if that is what people wish. That's why if I go on a chat show, I give them the very thing they want, and sometimes I go over the top. But I don't punch people any more: I'm too old for that now."
Born in Wimbledon, south London, he reached the peak of his career in the 1960s and 1970s in films such as Oliver!, where he played the evil Bill Sykes, and Women in Love.
He landed his first leading role in 1961 in Curse of the Werewolf and from then on was typecast as the villain. It was a role he took to with gusto.
At his home in the Irish village of Churchtown, in County Cork, Reed was loved by residents who treated his often ebullient behaviour with fondness. Regulars in the village's only pub, O'Briens, said he "liked his jar" and could be "a bit on the wild side when he had too much".
He moved to Ireland four years ago from Surrey with his second wife, Josephine, who was 26 years younger than him. She had been his companion since she was a 16-year-old schoolgirl.
His previous marriage was to the Irish model Kate Byrne, with whom he had a son, Mark. The marriage was dissolved in 1970.
Reed also had a daughter, Sarah, from a 12-year relationship with a ballet dancer, Jacquie Daryl.
But behind the explosive character, there was a professional who always knew his lines word perfect and was unfailingly courteous to colleagues and technicians.
He described himself as "only an actor - not a priest beyond reproach. I'm not a villain, I've never hurt anyone. I'm just a tawdry character who explodes now and again".Reuse content