Police said the girls would be interviewed by Riverside detectives once they were returned from San Bernardino. No further details were immediately released.
Diana Tourdot, 14, and Raylynn Bolt, 12, were both seen around midnight before they went missing. Donald Bolt, Raylynn's father, says Raylynn was sleeping over Diana's home near Magnolia and Arlington avenues.
Diana's mother said she fell asleep around 10:30 or 11 p.m., heard a noise around midnight and woke up at 6:30 a.m. and the girls were gone, according to Donald.
"This is the last thing a parent wants, is your kids to go missing," he said.
Bolt says his daughter is just like any other 12-year-old girl. He says he has no reason to think his daughter would want to runaway.
"We just all enjoy every day, I mean, we get along, we look forward to the next video games, the next PewDiePie on YouTube, you know," said Donald. "Unfortunately, I think these two girls just got into a little bit of trouble."
Raylynn had been hanging out with Diana for about six weeks. According to Donald, the two girls would spend a lot of time together.
On Sunday, family and friends spent all day searching for them with the help of police using bloodhounds.
"Extensive efforts have been made by police, family and friends to locate the two girls with no success," said Riverside police Sgt. David Amador.
On Monday, police ruled out the possibility of foul play and confirmed the young girls had ran away. Detectives said they were believed to have been spotted in the Riverside Plaza on the 3500 block of Central Avenue Sunday.
Bolt is 5 feet 6 inches tall, weighs 120 pounds and has dirty blonde hair and blue eyes.
Tourdot is 5 feet 6 inches tall, weighs 120 pounds and has dark brown shoulder-length hair and brown eyes.
Donald and Raylynn's brother, Jeremy, urged the girls to simply return.
"You guys can come home," he said. "You guys are OK. I mean, you know, if you guys maybe ran away or something or, you know, went to some guy's house, everything's fine. We've all done it. We've all been 12, 13, 14."
Anyone with information on their whereabouts was urged to contact Riverside Police at (951) 787-7911.
CNS contributed to this report.