Updated

Prosecutors are deciding whether to seek the death penalty against the man arrested in the murder of 5-year-old Samantha Runnion, the district attorney said Sunday.

Alejandro Avila was scheduled to be arraigned Monday on charges of abducting, sexually assaulting and strangling the girl, the Orange County prosecutor's office said.

Fox News has also learned more about the 27-year-old suspect's past. Avila's father apparently went to jail for killing his neighbor in a dispute that may have been racial. His brother was apparently shot in the back of the head and killed in Mexico.

District Attorney Tony Rackackaus said he would meet with Samantha's family as well as Avila's attorneys before deciding whether to seek capital punishment.

"After I review what they have to say with my staff and also review the evidence, then I'll decide whether or not to pursue the death penalty," Rackackaus said on NBC's Today show.

California law permits prosecutors to seek the death penalty against murder defendants if special circumstances exist, such as the commission of another crime.

DNA evidence found on Samantha's body matches Avila, police sources have confirmed to Fox News.

Orange County Sheriff spokesman Jim Amormino would not confirm or deny the report, but said authorities have evidence linking Avila, who was arrested Friday, to the crime.

In an interview with the Los Angeles Times before his arrest, Avila said detectives took a sample of his blood and photographed a scratch on his leg.

Funeral services for Samantha were pending. Late Saturday night her mother, Erin Runnion, broke a long silence and met with well-wishers in the courtyard of the townhome complex where a massive memorial of flowers, candles, cards and toys has appeared.

"You are truly wonderful to us," she said, and warned people: "Take care of your babies. Take care of each other's babies."

Samantha was playing with a 5-year-old friend just yards from her home when a man claiming to look for a lost puppy carried her away, kicking and screaming.

The swift arrest of Avila followed a massive effort by the police, press and public that began minutes after the first 911 call, Sheriff Mike Carona told The Associated Press Sunday.

Under the department's child-abduction emergency alert plan, a Southern California alert went out 10 minutes after the report that the girl had been snatched, he said.

"We were in everybody's front room, bedroom. People were seeing the task force number and we were getting thousands of calls. And it was those calls that led us to Avila," the sheriff said.

Carona said the department adopted the alert plan in 1999. It calls for an immediate countywide law enforcement alert and the notification of media. The alert plan was first used in March 2000 following the abduction of an 11-year-old girl from Laguna Hills. She was returned safely from Mexico.

"We drill from the top down as to how to respond. We have play books," Carona said.

Carona said the department plans to create a playbook for other law enforcement agencies. It also will review how it reacted in Samantha's case.

"We're going to figure out what our strengths were, what our weaknesses were and what we can do better." Carona said.

Carona has been criticized for saying early in the investigation that Samantha's body had been left "as a calling card" and that the killer might strike again within 24 hours.

"There was no shock value," Carona said in his own defense. "This is information the public has to understand. We don't want people to overreact. But we want people to understand we have a sexual predator out there."

Fox News' Adam Housley and the Associated Press contributed to this report.