(CNN) -- Richard Biggs, who played Dr. Stephen Franklin on "Babylon 5" and also had a long run on the soap opera "Days of Our Lives," died Saturday. He was 44, according to the actor's Web site.
A posting on a "Babylon 5" message board by J. Michael Straczynski, the sci-fi show's creator, said the cause of death has not been determined but that "paramedics who showed up suggested it was either an aneurysm or a massive stroke."
Biggs, a graduate of the University of Southern California School of Theatre, gained his first major exposure as Dr. Marcus Hunter on "Days of Our Lives." He was on the NBC show for five years.
He also appeared on Lifetime's "Any Day Now" and "Strong Medicine." Most recently, he played Clayton Boudreaux on the CBS soap opera "Guiding Light."
"Babylon 5" fans and staff were shocked by his passing.
"Richard was a consummate professional, but more than that he was an honorable, stand-up guy," Straczynski wrote in his posting. "He was, quite simply, a terrific guy, and everyone here is just devastated at the news."
Biggs is survived by his wife, Lori Gerber, and two sons.