As authorities continue to investigate Monday's mass shooting in Half Moon Bay that left seven people dead and one injured, officials on Tuesday said the massacre appears to be a case of workplace violence.
The mass killing took place at two mushroom growing locations, one at about 2:20 p.m. on San Mateo Road (Highway 92) and the other shortly thereafter along Cabrillo Highway South (Highway 1). Multiple victims were found at both scenes.
The suspect, 66-year-old Chunli Zhao, worked at the first shooting location, Mountain Mushroom Farm, and he either worked with or used to work with the victims at the shooting scenes, the sheriff's office said. Investigators believe he acted alone.
"All of the evidence we have points to this being the instance of workplace violence," San Mateo County Sheriff Christina Corpus said Tuesday.
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Zhao was taken into custody without incident at about 4:40 p.m. Monday in the parking lot of a San Mateo County sheriff's substation in Half Moon Bay after a deputy spotted his vehicle.
A semi-automatic handgun was found in Zhao's vehicle. The sheriff's office said the firearm was legally purchased and owned.
Zhao was booked into the Maguire Correctional Facility in Redwood City on seven counts of first-degree murder and one count of first-degree attempted murder, the sheriff's office said. Each count includes an enhancement for using a firearm. He is scheduled to be arraigned Wednesday afternoon.
"We're not going to be giving out a lot of precise detail on what was said," San Mateo County District Attorney Steve Wagstaffe said. "This is a case that is at the beginning stage. It has a long road to travel over the coming months and years. To that extent, we don't want to try it out in the public eye, but instead we will ultimately handle this case in one of the courtrooms."
Authorities did not immediately release information pertaining to Zhao's criminal history.
"There were no specific indicators that would have led us to believe that he was capable of something like this," sheriff's office spokesperson Eamonn Allen said. "He was not known to us or to have any sort of, again, indicators that may have led us to believe that this was something he might have done."
Five men and two women were killed in the shooting spree, the sheriff's office said. The injured victim, a man, was listed in stable condition as of Tuesday. The sheriff's office previously said there were seven male victims and one female victim.
All of the victims are Asian or Hispanic, according to the sheriff's office. Their identifies will be released publicly following notification of next of kin.
"As some of these victims were members of our migrant community, this represents a unique challenge when it comes to notifications and identifications," Corpus said.
Those impacted by the shooting gathered at a reunification center, where many stayed the night after the farms where they lived turned into crime scenes.
Local residents showed up at the reunification center to support the families affected.
"There's lots of tragedies hitting our country right now, more mass shootings than the number of days in a month, and to hit our small town is really shocking," Half Moon Bay resident Evany Sullivan said.
Half Moon Bay Mayor Deborah Penrose spoke with NBC Bay Area early Tuesday, saying something needs to be done.
"Too many guns," Penrose said. "Semi-automatic guns and automatic rifles need to be banned, period. There's no excuse for it."
President Joe Biden on Tuesday released a statement addressing the Half Moon Bay mass shooting, saying in part: "Jill and I are praying for those killed and injured in the latest tragic shooting in Half Moon Bay, California. For the second time in recent days, California communities are mourning the loss of loved ones in a senseless act of gun violence. Following a briefing from my homeland security team, I have directed my administration to ensure local authorities and the broader Half Moon Bay community have the full support of the federal government in the wake of this heinous attack. (Full statement below)
The shootings in Half Moon Bay marked California's second mass shooting in three days. On Saturday, a gunman opened fire at a dance studio in the Southern California city of Monterey Park, leaving 11 dead and nine injured.
Read President Biden's full statement below:
"Jill and I are praying for those killed and injured in the latest tragic shooting in Half Moon Bay, California. For the second time in recent days, California communities are mourning the loss of loved ones in a senseless act of gun violence.
"Following a briefing from my homeland security team, I have directed my administration to ensure local authorities and the broader Half Moon Bay community have the full support of the federal government in the wake of this heinous attack.
"Yesterday, Senator Feinstein — alongside Senators Murphy, Blumenthal and others — reintroduced a federal Assault Weapons Ban and legislation that would raise the minimum purchase age for assault weapons to 21. Even as we await further details on these shootings, we know the scourge of gun violence across America requires stronger action. I once again urge both chambers of Congress to act quickly and deliver this Assault Weapons Ban to my desk, and take action to keep American communities, schools, workplaces, and homes safe."
NBC Bay Area's Terry McSweeney, Marianne Favro, Pete Suratos and Stephen Ellison contributed to this report.