US actor RJ Mitte, best known for playing Walter White Jr. in the television series “Breaking Bad,” has died at the age of 34, according to media reports Monday.

Representatives for Mitte confirmed his death to US-based entertainment news outlets Variety and TMZ. The cause of death was not immediately disclosed.

Mitte portrayed the son of Walter White, played by Bryan Cranston, and Skyler White, played by Anna Gunn, in the AMC crime drama created by Vince Gilligan, which aired 2008-2013.

“It is with profound sadness that we share the tragic passing of beloved actor, philanthropist and passionate disability rights advocate RJ Mitte,” his representative said in a statement to Variety.

“Drawing from his own experience living with cerebral palsy, Mitte brought authenticity to the role and built a platform on disability awareness and inclusion.”

Beyond acting, Mitte advocated for people with disabilities, serving as an ambassador for United Cerebral Palsy and Shriners Children’s.

He also headed the Mitte Foundation, a charitable organization supporting philanthropic initiatives and challenging stereotypes about people with disabilities.

Following “Breaking Bad,” Mitte appeared in several television series and films, including “Switched at Birth,” Netflix’s superhero series “The Guardians of Justice,” the 2017 science fiction film “The Recall” and the 2020 thriller “The Oak Room.”

According to Variety, Mitte had been promoting his latest film, “Talking to Strangers,” and appearing on podcasts in the days before his death.

Several projects involving the actor were also in various stages of production and pre-production.