Kenneth Mitchell has died aged 49.
The Star Trek: Discovery actor passed away on Saturday (Feb 24), following a five-year battle with amyotrophic lateral sclerosis (ALS), a fatal motor neuron disease.
In a statement posted on X, his family said: "With heavy hearts we announce the passing of Kenneth Alexander Mitchell, beloved father, husband, brother, uncle, son and dear friend.
"Ken was widely known as an actor in many films and television shows. He's portrayed an Olympic hopeful, an apocalypse survivor, an astronaut, a superhero's dad, and four unique Star Trekkers."
Mitchell — who played the Klingons Kol, Kol-Sha, Tenavik and Aurellio on Star Trek: Discovery — had two children, Lilah and Kallum, with his wife Susan.
The statement continued: "Ken was diligent and hardworking in everything he did, but as a father these traits found their fullest expression. He was extremely dedicated to being a positive and playful force in the lives of his children.
"Regardless of his later disabilities, Ken discovered a higher calling to be more fully himself for his kids. Ken will be forever proud of who his children have become."
Mitchell was diagnosed with ALS in 2018 and he began using a wheelchair in 2019.
His family explained that the late actor — who played the father of Carol Danvers in Captain Marvel — was "grateful for the massive amounts of love and endless support he received" over recent years.
They said: "For five and a half years Ken faced a series of awful challenges from ALS. And in truest Ken fashion, he managed to rise above each one with grace and commitment to living a full and joyous life in each moment.
"Ken is forever grateful for the massive amounts of love and endless support he received from his community along this journey. Especially the courage, resilience and strength displayed from his extraordinary wife, family and friends."
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