A man accused of locking the entrances to a Southern California office building before shooting and killing four people he knew, including a 9-year-old boy, was charged in the attack Friday.
Aminadab Gaxiola Gonzalez, 44, is facing a host of charges in the Wednesday evening killings, including four counts of murder and two counts of attempted murder. Gonzalez, who was shot in the incident, is set to be arraigned Friday afternoon from his hospital bed.
Authorities say a man, two women and a boy were found dead and a third woman remains hospitalized in critical condition.
Police say Gonzalez knew his victims through business and personal relationships. Authorities said he locked gated entryways into an office suite that houses Unified Homes, a mobile-home broker, in Orange, about 30 miles south of Los Angeles, before opening fire.
It was the third high profile mass shooting in less than three weeks. The four victims were killed just a week after a gunman in Boulder, Colorado, killed 10 people at a supermarket. The week before that, a gunman in the Atlanta area killed eight people, most of them women of Asian descent, at three spas.
Police have yet to identify the victims in the attack, waiting first to notify their family and loved ones before their names are made public.
‘Horrific massacre’:Suspect locked entries, knew victims in deadly shooting at California office building, police say
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Victims were found in various areas of the building, including the boy, who was found dead in the arms of a woman believed to be his mother, officials said. That woman survived, authorities say.
“It appears that a little boy died in his mother’s arms as she was trying to save him during this horrific massacre,” Orange County District Attorney Todd Spitzer said Thursday. “I’m here to tell you that we’re going to do everything in our power in the Orange County District Attorney’s office to get justice for these families.”
The Orange Police Department started getting calls about a shooting around 5:30 p.m. local time Wednesday. Within two minutes, officers were on scene but discovered both entrances to a gated courtyard for the building had been locked with a bicycle cable lock, Lt. Jen Amat said.
The locks prevented officers from quickly entering the building while they continued to hear gunshots, Amat said. From outside the gate, officers opened fire at the suspect. She said bolt cutters, which were brought by sergeant who responded minutes later, were used to break through the locks.
Police scoured the building and the courtyard, where they found the suspect had been shot. He was in critical but stable condition at a local hospital as of Friday morning.

Police said it was unclear whether the suspect’s gunshot wounds were self-inflicted or from police.
“It appears all of the adults were connected either by business or a personal relationships,” Amat said Thursday. “This was not a random act of violence.”
Amat displayed a photo showing the suspect inside the business during a news conference Thursday afternoon, explaining police have video footage they are not releasing of him inside Unified Homes.
Amat said one firearm was recovered from the scene, a semi-automatic handgun. Police did not reveal when the gun was purchased or whether the suspect had obtained it legally.
Along with the gun, Amat said, a backpack was found that contained pepper spray, handcuffs and ammunition. He was living in a motel in Anaheim, northwest of Orange, and used a rental car to get to Unified Homes, Amat said.
Gonzalez was charged in 2015 in Orange County with cruelty to a child and other counts. It’s not clear if the child was his. He pleaded guilty to misdemeanor battery and served one day in jail. All other counts were dismissed, and the conviction was expunged in 2017, said Lauren Gold, spokeswoman for the city of Anaheim.
Contributing: Associated Press