The 66-year-old man suspected of killing four people at a mushroom farm in California and three others at a nearby site Monday was an employee of the farm, San Mateo County Sheriff Christina Corpus said Tuesday.
"All of the evidence we have points to this being the instance of workplace violence," the sheriff said. "The only known connection between the victims and the suspect is that they may have been coworkers."
The killings mark California's second massacre in three days involving Asian American victims and suspects. The San Mateo County victims were either Asian or Hispanic, Corpus said.
In California, 19 people were slaughtered in three mass shootings in just 44 hours:
• Seven people killed Monday in the Half Moon Bay area near San Francisco;
• One person killed and seven others wounded Monday evening in Oakland.
While the motives remain a mystery, the Half Moon Bay killings bear some similarities to the carnage in Monterey Park. That's where 72-year-old Huu Can Tran gunned down 20 people -- killing 11 -- during Lunar New Year weekend celebrations, authorities said.
Both cases share ties to the Asian American community. And the shooter or suspect in each is of Asian descent and far older than the 33-year-old average age of mass shooting perpetrators, according to the Rockefeller Institute of Government.
In San Mateo County, suspect Chunli Zhao was taken into in custody about two hours after the first call to police while he was parked at a sheriff's substation with a semi-automatic handgun in his vehicle, the sheriff said.
"Some of the victims were Chinese, that the perpetrator was Chinese and that this was an agricultural community -- they were agricultural workers," Half Moon Bay Mayor Deborah Penrose said Tuesday.
Officers in San Mateo County found four people dead and one person wounded at a mushroom farm. Moments later, three more people were found dead near a trucking facility about two miles away in Half Moon Bay, county officials said. Authorities identified those killed as five adult men and two adult women, adding that the the person wounded was a man who is being treated at a trauma center for his injuries.
Zhao was a "co-worker or former co-worker" of the victims at each shooting site, the sheriff's office said in a news release.
That same evening, yet more bloodshed unfolded -- this time in the Bay Area city of Oakland. One person was killed and seven more wounded were in stable condition, police there said.
Suspect lived on first property
The sheriff said the attack was "a workplace violence incident" in which the suspect targeted specific people.
"He had an opportunity, we do believe, to hurt other people, but he had targeted individuals that he went after and pursued," Corpus told CNN's Erica Hill and Jim Sciutto Tuesday morning.
The gunman lived on the first shooting site, a company spokesperson told CNN. That property, formerly known as Mountain Mushroom Farm, was acquired by a company called California Terra Garden in March 2022, and there were several mobile homes and trailers for employees on the property, said spokesperson David Oates.
The suspected gunman had lived there since at least March, though he had been working on the farm for longer, Oates said.
The farm grows mushrooms and "other food-grade herbs" like basil and oregano, Oates said.
All employees "had background checks, and there was nothing to indicate anything like this was even a possibility," the spokesperson added.
In a statement responding to the attack, California Terra Garden said it was "shocked and grief-stricken over the senseless loss of four of our friends and long-time employees, and we pray for the team member that remains in critical condition."
No previous red flags, sheriff says
The suspect, who was not known to local law enforcement prior to the shooting, had legal possession of a semi-automatic weapon that was registered to him, the sheriff told CNN Tuesday morning.
Prior to this week, the shooting suspect "wasn't a red flag," Corpus said. "There was nothing that would have kind of elevated or raised us to have any concern with him at this time, prior to this incident."
The sheriff added the attack highlights a need for discussion around mental health issues.
"This is one of these issues where someone snaps, unfortunately, and innocent people were killed," the sheriff said.
"We just have to look at it from a multi-pronged approach, because it's not just the guns, it's also the individuals that have access to guns and those individuals that are suffering from mental illness or mental stressors," she added.
'I'm still scared'
An employee of the mushroom farm still working to come to terms with the violence that unfolded told CNN he ran for cover when the suspect opened fire and then saw the shooter flee the scene on a forklift.
"I'm still scared trying to figure out what happened," said the employee, who asked not to be named because of the ongoing law enforcement investigation. "I don't understand."
The employee estimated that roughly two dozen people work at the farm. About half a dozen are Chinese while the rest are Latino immigrants and the two groups often communicate through hand gestures or a translator because of language barriers, he said.
The employee told CNN he and Zhao were coworkers at the farm and both were working on Monday. He said he had known the suspect for roughly six years and had considered him to be "very friendly" and a "nice guy," adding he didn't know what may have prompted the attack.
When he heard gunshots, the witness said he tried to hide with several other coworkers, worried that the gunman may shoot in their direction. Then, the employee ran to one victim outside of a greenhouse, but saw how much the individual was bleeding and realized "it was too late."
When the gunfire stopped, the witness told CNN he saw the suspect drive away from the scene on a forklift.
'Tragedy upon tragedy'
California Gov. Gavin Newsom was at a hospital meeting wounded victims of the Monterey Park shooting when he was "pulled away to be briefed about another shooting -- this time in Half Moon Bay," he said.
"Tragedy upon tragedy," Newsom tweeted.
The governor will visit Half Moon Bay on Tuesday to meet with families of those killed in the San Mateo County massacre.
President Joe Biden reiterated his call for Congress to "act quickly" and ban assault weapons. "We know the scourge of gun violence across America requires stronger action," he said in a statement Tuesday.
The mayor of Monterey Park, still dazed by the slaughter in his city, gave his condolences to those grieving in Half Moon Bay.
"I know what is in store for them in the next few days," Mayor Henry Lo said, offering his support during their "long road of recovery."
The San Mateo County mushroom farm's owners had no knowledge of the gunman nor his motive, they said.
"We are shook and very eager to gain more information from the authorities and their investigations," Concord Farms said in a statement to CNN. "Our hearts are with the victims, their families and the Chinese American community -- from Half Moon Bay to Monterey Park."
Flood-ravaged community faces new horror
The Half Moon Bay community must unite in healing -- and support each other to address gun violence -- San Mateo County Supervisor Ray Mueller said.
"There were farmworkers affected tonight; there were children on the scene at the incidents. This is a truly heartbreaking tragedy in our community," Mueller said.
Mueller spoke to the mental health toll the violence has unleashed in the community and urged people to seek help, especially as the city has been trying to recover from the impact of recent deadly flooding that stretched across large swaths of the state.
"Please take advantage of the mental health crisis counseling that is available," he said, adding anyone can reach out to the county's hotline. "You are not alone."
Half Moon Bay Vice Mayor Joaquin Jimenez also urged residents to seek mental health counseling.
"This is something that we get to watch on the news. Never think that it's gonna come and hit home," Jimenez said. "Today, we are the news. Our community has been affected."
Correction: An earlier version of this story gave the wrong age for Chunli Zhao. He is 66.
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