Fairfield police arrested Sergio Santiago Cabada, 18, around 3:30 p.m. Monday on suspicion of making terrorist threats. He was booked into jail around 6:30 p.m. that day and was being held on $15,000 bail.
Cabada's father was home when police went to the family's residence, Fairfield police Sgt. Kevin Carella said.
"His dad was mortified his son had made the comments and that police were at his home," Carella said.
Cabada's father was aware of the comments on his son's Facebook page and had talked to him about them before police arrived, Carella said.
Police said Cabada had posted comments stating that he supported the actions of the shooter, 20-year-old Adam Lanza, at Sandy Hook Elementary School in Newtown, Conn., and had thought about the possibility of committing similar acts.
The massacre claimed the lives of 20 children and six adults at the school.
Police confiscated four hunting rifles and some ammunition from Cabada's residence for safekeeping, Carella said.
On Saturday, Cabada posted an apology on his Facebook page.
"I apologize for what I said, at the time I was not aware of the huge implications of what I said and I was merely curious and slightly experimental in my terms," Cabada said.
"I am particularly sorry if I offended anybody personally. I did not say this with evil intentions, I was merely being a stupid 18-year-old being edgy and cocky on a social networking website," Cabada wrote.
Cabada said in the post that after he later thought "deep and hard about the tragic loss of those children from many different perspectives," he understood "the impact of such an emotional event."
In response, Carella said today, "You can't do certain things and take them back."
Cabada has no prior contacts with police, Carella said.
Carella said Fairfield police on Monday sent their report to the Solano County District Attorney's Office, which will decide whether or not to charge Cabada.
