Harry Potter’s Daniel Radcliffe has paid tribute to the man who made his character’s life hell on screen: veteran British actor Alan Rickman.

Rickman passed on Friday aged 69 after an 18-month battle with cancer, his death capping off a tragic week for the British entertainment industry in which it also lost singer David Bowie.

In a rare social media post, Radcliffe described his relationship with Rickman, who he said was the first older actor on the Harry Potter set to treat him as a peer rather than a child.

“[Alan] was so encouraging of me both on set and in the years post-Potter. I’m pretty sure he came and saw everything I ever did on stage both in London and New York. He didn’t have to do that,” he wrote.

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“It might surprise some people to learn that contrary to some of the sterner (or downright scary) characters he played, Alan was extremely kind, generous, self-deprecating and funny.

“And certain things obviously became even funnier when delivered in his unmistakable double-bass.”

Rickman played baddie Severus Snape for 10 years. Photo: Getty

Rickman acted opposite Radcliffe from 2001–2010 in all eight of the Harry Potter films. When Radcliffe started in the series, he was just 11 years old.

“Working with him at such a formative age was incredibly important and I will carry the lessons he taught me for the rest of my life and career,” he said.

“Film sets and theatre stages are all far poorer for the loss of this great actor and man.”

Fellow Harry Potter crew including JK Rowling and Emma Watson also posted their own tributes to Rickman, Watson saying “I’ll really miss our conversations”.

While Rickman was best known to the younger generations as Severus Snape the cruel potions teacher, he was known to older generations for his roles in Die Hard, Love Actually and Sense and Sensibility.

My thoughts are with Rima and the rest of Alan’s family. We have all lost a great talent. They have lost part of their hearts.

— J.K. Rowling (@jk_rowling) January 14, 2016

#AlanRickman pic.twitter.com/fwMvp0lmiX — Emma Watson (@EmWatson) January 14, 2016