Updated

Deputies opened fire at a charging pit bull and one bullet apparently ricocheted off the ground and killed a 17-year-old boy who had been helping to restrain the dog, authorities said Thursday.

The dog, which belonged to the boy's neighbor, had already bitten one of the deputies and the teen had restrained it behind the apartment complex when it broke loose and charged again, Los Angeles County sheriff's officials said.

Deputies shot and wounded the dog when it was about 10 feet (3 meters) away, then chased it as it tried to run back behind the building, officials said. Only then did they see that the boy, who had been standing about 40 feet (12 meters) away, had also remerged from behind the building and had been hit in the chest by a so-called "skip round" that had ricocheted off the pavement. He died at a hospital about an hour later.

The boy's mother, Roberta Alcantar, said his name was Armando Garcia-Muro, the eldest of four siblings about to start his senior year of high school. She said he loved dogs and planned to go into construction.

"He would give his life for anybody," Alcantar told the Los Angeles Times. "He was a very loving person."

Sheriff's Capt. Christopher Bergner called it an "extremely, extremely unfortunate incident," adding that it didn't appear the deputies saw the teen in the dark before they fired.

The deputy that had been bitten was also hit by a fragment that had struck the ground but had only minor injuries, officials said. He was not among those that fired. Two of the five deputies at the scene shot at the dog, officials said.

The pit bull was captured and animal control planned to euthanize it.

The deputies had first been called to the Palmdale complex at about 3:45 a.m. with complaints of a loud party.

Sheriff's officials said in a statement and at a news conference that they found evidence of several shots having ricocheted off the ground, and concluded that one of those most likely killed the teen.

They did not elaborate further, and a message left with one of the homicide detectives on the case was not immediately returned.