Dave Prowse, the British actor behind the menacing black mask of Star Wars villain Darth Vader, has died, his agent Thomas Bowington said Sunday.

"It's with great sadness that we have to announce that our client Dave Prowse... passed away yesterday morning at the age of 85," Bowington wrote on Facebook.

"May the force be with him, always!" the agent told the BBC.

Bowington added that Prowse's death was "a truly and deeply heart-wrenching loss for us and millions of fans all over the world".

Mark Hamill, who played Luke Skywalker in the epic saga, tweeted that he was "so sad to hear David Prowse has passed."

"He was a kind man & much more than Darth Vader," he wrote.

"Actor-Husband-Father-Member of the Order of the British Empire-3 time British Weightlifting Champion. He loved his fans as much as they loved him."

A former body-builder turned actor, Prowse's towering stature at almost two metres clinched him the role of the instantly-recognisable antagonist in the original Star Wars trilogy.

But while he donned the glossy black armour and cape, the Bristol native's strong western English accent meant the filmmakers turned to James Earl Jones for the chilling voice that would emerge from behind the mask.

Prowse nevertheless remained attached to the character, telling AFP in 2013 that he was "the greatest big-screen villain of all time".

He was born in the southwest English city on July 1, 1935, to a working class family, winning a scholarship to the prestigious local school.

Prowse soon developed a love for weightlifting and went on to represent his country at the Commonwealth Games in the early 1960s before forging a career in Hollywood.

He trained Christopher Reeve for the role of Superman and was reportedly spotted by Star Wars director George Lucas as an extra in "A Clockwork Orange".

Lucas asked him to audition for the roles of Vader and hairy giant Chewbacca, plumping for the dark side because "you always remember the bad guys," he once told the BBC.

At home, he is equally well remembered for playing the "Green Cross Code" Man, a superhero created as part of a public information campaign to teach children road safety.

He played the role for almost 20 years, and earned an MBE in 2000.

Other film credits include 1972's "Minotaur" and 1977's "Jabberwocky", and he also appeared in many TV shows including "The Saint" and "The Benny Hill Show".

Since the original Star Wars trilogy was released in the late 1970s and early 80s, Prowse had travelled the world meeting hardcore fans.