Gilbert Prieto told KOB-TV ( http://bit.ly/1p2f1uE ) that he has no idea what prompted the beatings, and that he and his family had once been homeless themselves.
"It's so hard that he could do that to someone where... I mean, like I said, we came from there," said Prieto, the father of the 15- and 16-year-olds accused. "You know what I mean? We're not there now, but that's where we... We got out of there," Prieto said.
According to the criminal complaint, the teens came home from a party and one of them was "very angry" over a breakup with a longtime girlfriend. So they covered their faces with black T-shirts and went out to look for someone to beat up and possibly rob.
The attack was so brutal it stunned even veteran police officers
"I personally, after reading that complaint, was sick to my stomach because of the nature of the violence and the age of the offenders," police spokesman Simon Drobik said.
Officers responded Saturday around 8 a.m. to a 911 call reporting the two bodies in a field. They found one victim lying on a mattress and another lying on the ground. Jerome Eskeets, a third victim who said he was able to flee, was hospitalized for his injuries.
Eskeets told police that he recognized one of the "kids" hitting and kicking him as someone who lived in a house nearby, and police found the trio of suspects there. Prieto said the 15- and 16-year-old were his sons and Rios was a friend who had spent the night.
The complaint says Rios has been charged with two counts each of murder, among other charges. The younger boys will likely be charged with murder as adults, Drobik said. The Associated Press is withholding their names because of their age.
Rios told investigators he acted as a lookout while the other boys attacked both men with bricks, sticks and a metal fence pole. The younger suspects, however, told police that Rios also took part in the attacks.
Investigators have not yet confirmed the identities of the two victims, although police did find an Arizona driver's license at the home where the boys were. Their transient background and the severity of their injuries have made identifying them difficult, Drobik said.
The department is asking anyone in the homeless community with information about other attacks to get in touch with them. Drobik said any transients uncomfortable approaching police can also contact them through any social service agency.
"Just please come forward," Drobik said.