Tributes from co-stars and fellow entertainers have poured in for British actor and director Alan Rickman, who has died at the age of 69.

Among them was Harry Potter star Daniel Radcliffe, who was antagonist to Rickman's Prof Severus Snape throughout the series.

He described Rickman as "undoubtedly one of the greatest actors I will ever work with", and said the icon had been supportive of his career since first being cast as the boy wizard at the age of 11.

Read: Alan Rickman: A life in pictures

Harry Potter author JK Rowling and fellow Potter actors Emma Watson, aka Hermione; Matthew Lewis, aka Neville Longbottom; and Jason Isaacs, who played Death Eater Lucius Malfoy have also paid their respects on social media, with Isaacs describing him as "hilarious, tragic, terrifying and truthful all at the same time".

Lewis said he had been an "inspiration", while Watson wrote on Facebook that she felt "so lucky" to have worked with Rickman.

"I'll really miss our conversations. RIP Alan. We love you," she added.

Rupert Grint, who played Harry's sidekick Ron Weasley, said:

Rickman's long-time friend and colleague Emma Thompson, who worked with him on a number of projects including 2003's Love Actually, said her tribute was "hard to write because I have just kissed him goodbye".

She called him "the ultimate ally" in life, politics and art, and said she trusted him absolutely.

Sir Ian McKellen described Rickman as "matchless", revealing Rickman took great interest in those with whom he worked - campaigning for better food for crew members and berating a director who dared criticise McKellen too harshly.

"There is so much that is matchless to remember about Alan Rickman. His career was at the highest level, as actor on stage and screen and as director ditto," he wrote.

Dame Helen Mirren, who starred alongside Rickman in a stage performance of Anthony and Cleopatra, described him as a "towering person - physically, mentally and as an artist."

"He was utterly distinctive, with a voice that could suggest honey or a hidden stiletto blade, and the profile of a Roman Emperor," she added.

"He was also a great friend, generous and social. He will be very missed by many.”

And Lindsay Duncan - with whom he starred in an adaptation of Noel Coward's Private Lives - paid her respects to the man she said have her "some of the greatest joy of my professional life", adding:

"As a friend, he was without equal. So many of us have a lost the most generous and loyal friend imaginable. What a man."

Speaking on the red carpet at The Revenant premiere, Domhnall Gleeson - who played the eldest Weasley brother, Bill, in the Harry Potter films - paid tribute to the man he said "was able to do everything well."

The Revenant star Leonardo DiCaprio also stopped to honour the actor, saying his death was a "huge loss."

"He seemed like an amazing man," he added.

Other tributes have rolled in from stars of the stage and screen.

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