He was 49.

He reportedly died due to complications from amyotrophic lateral sclerosis or ALS.

On the actor's official Instagram page, a statement was posted by his family members: "With heavy hearts we announce the passing of Kenneth Alexander Mitchell, beloved father, husband, brother, uncle, son and dear friend."

As per the statement, he died on Saturday.

The actor was diagnosed with ALS in 2018.

In recent years, his family members often posted updates on his health conditions.

The actor marked the fifth anniversary of his health condition recently with an Instagram post. "My brother humorously mentioned that they don’t really have a happy ALS Anniversary card in the shop. However, I want to celebrate today; the gift of life. I’m so thankful to have this day in front of me. It’s been a long 5 years. So much lost, so much gained. Incredibly hard times, mixed with so many more blessings. At the heart of it all are friends and family, caregivers and doctors coming to the aid of my family over and over and over again. Giving a plethora of support and love and care and encouragement. There is so much beauty in that. This disease is absolutely horrific…yet despite all the suffering, there is so much to be grateful for. Especially the little joys and resilience of today and the hope of a tomorrow."

Kenneth Mitchell was known for his role as Eric Green in the CBS television series Jericho (2006–2008) and for portraying various characters in Star Trek: Discovery (2017–2021).

He played the character of Joseph Danvers in Captain Marvel (2019).

What is ALS?

As per Mayo Clinic website, ALS  is a nervous system disease that affects nerve cells in the brain and spinal cord. ALS causes loss of muscle control.

The disease gets worse over time.