Kenneth Mitchell, a Canadian actor known for his roles on the series Star Trek: Discovery and the film Captain Marvel, died on Saturday. He was 49. His family members confirmed his death by sharing an official statement on social media. Diagnosed with ALSCanadian actor had lived with the neurological disorder amyotrophic lateral sclerosis, or ALS, which causes paralysis and death, for more than five years. Kenneth faced a series of awful challenges from ALS. According to his family, Kenneth handled the situation with grace and dedication. View this post on Instagram A post shared by Kenneth Mitchell (@mr_kenneth_mitchell)Best known forKenneth Mitchell played the Klingons Kol, Kol-Sha and Tenavik, as well as Aurellio, on Star Trek: Discovery, and worked on several other characters in an episode of Star Trek: Lower Decks. He played the role of father of the superhero, Carol Danvers in Captain Marvel. He also played the role of Eric Green on the series Jericho, Joshua Dodd in the series Nancy Drew, and appeared in several other film and television series. View this post on Instagram A post shared by Kenneth Mitchell (@mr_kenneth_mitchell) What is ALS It is a nervous system disease that weakens muscles and impacts physical function. In this disease, nerve cells break down, which reduces functionality in the muscles that they supply. The cause is unknown. The main symptom is muscle weakness. However, medication and therapy can slow ALS and reduce discomfort, but theres no cure.