When 2-year-old Samuel Zamudio's grandmother came home and asked where the toddler was, family members frantically searched every room and even asked neighbors if they'd seen him.
Finally, the grandmother, 42-year-old Eustulia Zamudio, tried the backyard and screamed.
Lying in the dirt, his clothes torn from his body, was Samuel's mangled, lifeless body. Police said the five pit bull mixes Zamudio kept out back had fatally mauled the boy.
PHOTOS: Toddler mauled to death by pit bulls
"We just don't have an explanation," said Erica Vega, a family friend who was one of the adults at the house on Citrus Street in Colton when the attack occurred. They said Samuel might have gotten into the yard through a back window. "He could have fallen down. The dogs just could have taken him."
Colton police said the boy was "suffering from extensive wounds to the upper body" when he was rushed to Arrowhead Regional Medical Center, where he was pronounced dead about 6 p.m. Monday.
Witnesses said Samuel's uncle, 23-year-old Marco Zamudio, tried to resuscitate him until paramedics arrived. Eustulia Zamudio alerted the family.
The two were arrested on suspicion of child endangerment resulting in death. Police said that Samuel's uncle was responsible for the toddler, and that Eustulia Zamudio owned the dogs and the property where the attack occurred. They are due in court Wednesday.
Five adults and three children lived in the home, including Vega's 3-year-old daughter and 1-year-old son. In addition to the five pit bull mixes in the back, two other dogs were in the house and fenced in the frontyard.
The five dogs believed to be involved in the attack were being held at a San Bernardino animal shelter and will probably be euthanized, police said.
Vega, whose husband grew up with the family, said she had never liked the dogs, but didn't worry about her safety or her children's.
"They were not aggressive," she said. "They were not fighters."
Neighbor Janeth Cardiel said her father had complained to animal control officials about four months ago.
She said he complained that the dogs were loud and, in the summer heat, that the smell of their waste was unbearable. The dogs didn't seem violent, she said, just restless and starved for attention.
On Tuesday, standing in the living room, Vega said an empty feeling pervaded the typically bustling house: The grandmother and uncle were in custody, the dogs were gone. She missed Samuel, who was lovingly called "Eli."
Although he didn't live there, he was there frequently and was so full of life, she said. He loved jumping on her bed. "He was so awake, alert, energetic," she said. "He was an amazing kid. An amazing kid."
In the house, a photograph of Pope John Paul II hangs on one wall, and another of Pope Francis is taped to the front door, right above the notice posted that the dogs had been seized.
A small altar, with candles and images of the Virgin Mary, had been set up in the living room. In the center was a picture of Eli with his brothers, ages 1 and 7. Eli was smiling.
"We still hope this is a dream, and we're trying to wake up," Vega said. "Wake up and see him there."
Monday's incident is at least the second dog attack in Colton this year. In April, officers shot a pit bull after it attacked its owner and killed another dog.
In May, a fatal attack in the Antelope Valley increased pressure on lawmakers to hold dog owners accountable for such incidents. The Los Angeles County Board of Supervisors unanimously agreed this month to strengthen county regulations against vicious dogs.
In Riverside County, supervisors are proposing an ordinance that would require all pit bulls and pit bull mixes in unincorporated cities to be sterilized.