John Furia Jr., seen in this 1972 photo, has died at the age of 79. The prolific screen and television writer wrote for a number of popular television shows including Bonanza and Hawaii Five-O. John Furia Jr., seen in this 1972 photo, has died at the age of 79. The prolific screen and television writer wrote for a number of popular television shows including Bonanza and Hawaii Five-O. (Jeff Robbins/Associated Press)

Prolific Hollywood writer John Furia Jr., who wrote for the popular television series Bonanza, The Twilight Zone, The Waltons, Dr. Kildare and Hawaii Five-O, among other shows, died Thursday night at the age of 79.

The Writers Guild of America West announced Furia's death in a news release on Friday. The cause of death had not yet been determined.

A longtime advocate for Hollywood writers, Furia was a former president of the guild, and chaired and co-chaired its negotiating committee several times.

"He was a tireless advocate in the cause of improving the economic and professional status of writers," former WGA West president Daniel Petrie Jr. told Variety magazine.

Furia began his career in the entertainment industry singing with bands in New York City before moving to California.

He also wrote for the big screen, writing hits such as The Singing Nun, which starred Debbie Reynolds and Greer Garson.

He was founding chairman of the University of Southern California's School of Cinema-Television Writing Division, where he taught screen and television writing.