BROWNSVILLE, Texas — Actor and disability-rights advocate RJ Mitte, best known for portraying Walter “Flynn” White Jr. on AMC’s Breaking Bad, died Monday in Brownsville, Texas. He was 34.

Cameron County Justice of the Peace Cyndi Hinojosa told The Associated Press that she pronounced Mitte dead at about 1:30 p.m. Monday and that an autopsy would be performed. His representatives confirmed his death and said Tuesday that he died by suicide. The official medical findings were not immediately available.

Mitte, who had cerebral palsy, appeared throughout the five-season run of Breaking Bad as the son of Bryan Cranston’s Walter White and Anna Gunn’s Skyler White. He drew on his own experiences with disability, physical therapy and family pressures in developing the character.

Beyond acting, Mitte used his public profile to advocate for disability awareness, inclusion and better representation in entertainment. His representatives described him as an actor, philanthropist and disability-rights advocate who worked to challenge stereotypes. Reuters reported that Cranston was among those paying tribute.

Mitte also appeared in Switched at Birth and other television and film projects. His performance on Breaking Bad helped bring a disabled character—played by an actor with the same disability—to one of television’s most widely recognized dramas.

If you or someone you know is in crisis in the United States, call or text 988 to reach the Suicide & Crisis Lifeline. Help is also available at 988lifeline.org.