Game of Thrones star Alfie Allen has now spoken up about the sudden death of Andrew Dunbar, an actor who worked with him on the HBO fantasy series. Dunbar, who was in his 30s, reportedly died in his Belfast, Ireland home on Dec. 24.

In an Instagram story published Saturday, Allen wrote that he was "extremely shocked and saddened to hear" of Dunbar's death, adding, "To lose a loved one so young, I can only imagine what his family are going through."

Details about Dunbar's death are not clear, but police have revealed it was "not suspicious."

In addition to working as a body double for Allen's character Theon Greyjoy and as one of the House Stark bannermen on Game of Thrones, Dunbar was also a DJ and worked on other series such as Derry Girls, Line of Duty, and Krypton.

Dunbar's casting agency The Extras Dept. posted a tribute to him on Facebook, writing, "We have so many fond memories of the years Andrew worked with us. He was so versatile we could cast him in anything, he was such a talented performer he would always end up being featured, and he was so adored that he was always requested by productions again and again. He'll be remembered in his roles as a Stark and Theon Greyjoy's Double on Game of Thrones, a corrupt Police Officer on Line of Duty, the poor fella cornered by Colum on Derry Girls, and a Rebel on Krypton to name a few. But most of all he'll be remembered by his kind soul and infectious personality."

Fellow Game of Thrones actor Andrew McClay, who was prominently featured in Game of Thrones: The Last Watch, also honored Dunbar's memory in a statement to Belfast Live. "Everyone always wanted Andrew. There was just something about him that was special. People always felt good around him, happy, excited for the day's work and there was always a lot of fun when he was around," McClay said. "I'd say most of us felt the same when we came on set, we wanted Andrew to be there, we'd search him out. He was like a gel that kept us all together."

Meanwhile Game of Thrones' head of crowd makeup Pamela Smyth told the publication, "Even among the thousands of extras that came through the crowd room on Thrones, Andrew always stood out. Always professional and mannerly with a big broad beaming smile. A beautiful soul — he will be missed by all the GOT family."

Following the news of his death, Dunbar's colleagues and friends have continued to honor him through their social media tributes.

View this post on Instagram

Initially I wasn't going to post anything but now I see the value in everyone sharing their thoughts on the loss of a good friend Andrew Dunbar, who died on Christmas Eve. It's good and healthy for us to share our memories of him and to know we are not alone in our grief. I have found it comforting to read what everyone has been posting in the past few days. For me, it really is simple. He made me smile, he made me laugh and he made me think. He was just so damn loveable. I saw him only a week ago and we hugged as he left. I'm grateful for that hug and I am grateful to have known him. I am sorry for the people who are grieving tonight and sorry for the people who never got a chance to meet him. He was one of the good ones. Look after each other. If you need help, please talk to someone. Anyone. You are never alone.

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