Paul Flores was charged with first-degree murder in the killing that allegedly happened as he tried to rape Smart in his dorm room at California Polytechnic State University campus in San Luis Obispo after a party. He is now also facing two sex assault charges in Los Angeles.
His father Ruben Flores is charged as an accessory after murder.
Their arraignments and bail hearings were postponed until Monday.
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Smart's family released the following statement on the arraignment delay:
"After nearly 25 years of waiting, today's delay in the arraignment process was not unexpected or surprising. Make no mistake, we have begun the final quest to bring justice for Kristin. We know we are in good hands with the San Luis Obispo County District Attorney's office, and we will wait patiently for the process to commence."
Flores has lived in the San Pedro, California, area since around 2005.
When San Luis Obispo County District Attorney Dan Dow discussed the case on Wednesday, he said Flores frequented bars in the San Pedro area and may have committed other sexual assaults. He urged the public to come forward with information.
The DA has indicated that evidence of other sexual assaults committed by Flores may become part of the Smart case.
Kristin Smart case: Suspect Paul Flores also facing sex assault allegations in Los Angeles
"If you've been a victim in another location, perhaps in San Pedro, we want you to come forward to law enforcement so that you can get assistance that you need and it may help us in this particular case as well," he said.
San Luis Obispo County Sheriff Ian Parkinson said Paul Flores was being held on no bail after he was arrested for murder and transported brought back to the county. His father was being held on $250,000 bail.
The Associated Press contributed to this report.