Gareth Thomas, the star of the cult sci-fi series Blake's 7, has died at the age of 71.

The actor, best known for playing intergalactic resistance leader Roj Blake in the 1970s BBC show, died of heart failure yesterday.

A message announcing his death was posted on the Blake's 7 website last night.

The statement said: "It is with deep sadness that we have to announce that Gareth Thomas passed away this morning, 13th April 2016, from heart failure.

"Our thoughts are with his wife Linda, and his family and friends."

His death was confirmed by friend Andrew Mark Sewell, who worked as a producer on the reboot of Blake's 7.

He lived in the Scottish Borders for many years before moving to Surrey in 2009.

Born in Wales in 1945, Rada-trained Thomas made his acting debut in 1965, before taking small roles in well-known series such as The Avengers, Z Cars and Coronation Street.

In 1972 he was nominated for a television Bafta for his performance in the BBC Play for Today, Stocker's Copper, and nominated again for his role as a Welsh hill farmer in BBC One's Morgan's Boy in 1984.

He earned a legion of young fans as Adam Brake, an astrophysicist who brings his son to the strange village of Milbury to study standing stones in eerie BBC children's drama The Children Of The Stone.

But Thomas's most famous role was as political dissident Roj Blake, the leader of a group of rebels fighting against the totalitarian Terran Federation, in Terry Nation's sci-fi drama Blake's 7, which drew in up to 10 million viewers a week in the UK.

He was cast in the show in 1978 and stayed for two series, until he insisted his character be killed off to the dismay of fans. However, he returned for the show's climactic final episode.

Thomas's other credits include London's Burning, Heartbeat, Midsomer Murders and Doctor Who spin-off Torchwood.

He was also a seasoned stage actor, appearing in numerous Royal Shakespeare Company and English Shakespeare Company productions.

He returned to his role as Blake in 2012 in The Big Finish's audio series Blake's 7: The Liberator Chronicles.

Fans and celebrities took to Twitter to pay tribute to the star.