Guy Edward Bombing at Palm Springs Fertility Clinic Saturday.

Richard Bartkus said he hasn't spoken to his 25-year-old son for more than a decade and he is not the one he remembers.

"He tried to help people," Battercus said of his son. "After twenty palms, he just changed."

He didn't realize his son was a suspect in a massive investigation across Southern California on Saturday, which is still under his son's home in Twenty-Ten Palm Trees. He hadn't realized that his son had died after the incident.

"It doesn't say he's dead, I read that he's dead later," Bartkus said in a conversation with CBS News Los Angeles.

FBI investigators say Guy Bartkus filled his 2010 Silver Ford Fusion before driving an hour-long drive to Palm Springs, which they believe he deliberately parked outside the American Reproductive Center at the IVF clinic.

Investigators say they are still digging out a series of Bartkus’ online posts and works, which seem to indicate anti-family nationalism beliefs that people should not continue to have children.

“We need public help to determine the gap in the investigation,” Akil Davis, assistant director of the FBI’s Los Angeles field office, said at a Sunday press conference. “We know where Mr. Bartkus was around 6 a.m., and we know the timeline of when he entered the city, but we need public help to determine where he was traveling through the city before the explosion.”

As the investigation continues, Bad Cuth said his son is fascinated by the way he worked as a child. Bucktus also said that when his son was nine years old, he accidentally burned his family home while trying out the game’s tricks, but never noticed any red flags.

"He would make smoke bombs, stinky bombs, kids," his father said. "He didn't cause anything dangerous. When I say bombs, it's not like a bomb. It's like you just throw something on the ground and pops up."

Battercus said bombing a building, what the FBI now calls the biggest in Southern California history, is what he never imagined his son would do.

"I don't know what changes... maybe it was a girl, maybe he was hanging out there. Not him. Until then, Guy was more about helping people."

Federal investigators say they are dealing with the investigation as an act of international terrorism. They don't have a timeline for when neighbors around the twenty-palm houses in Bartkus will reopen when they continue to collect evidence.