Authorities have said the firearm was "modified," the Los Angeles Times reported, but they have not clarified exactly how it was altered.
What did Newsom say?
Despite California having the "strictest gun control laws in the U.S.," according to O'Donnell, Newsom said that he is not surprised the mass killing happened.
Then he disparaged the Second Amendment and gun owners.
"Nothing about this is surprising. Everything about this is infuriating," Newsom told O'Donnell. "The Second Amendment is becoming a suicide pact."
A suicide pact, of course, is a mutual agreement between at least two people to commit suicide together. Newsom is thus asserting that the Second Amendment, which affords Americans the right to possess firearms, ultimately leads to death. Ironically, Newsom made his comments as armed security protected him.
But O'Donnell quickly pushed back and defended Americans.
"But there's many people in this country that support the Second Amendment and are lawful gun owners," she told Newsom matter-of-factly.
"Yeah, I have great respect — I have no ideological opposition to someone who is reasonably and responsibly owning firearms and getting background checks and being trained," Newsom claimed in response.
California Gov. Gavin Newsom talks to Norah O'Donnell about Monterey Park shooting, gun lawswww.youtube.com
Despite claiming that he has "no ideological opposition" to gun ownership, Newsom appeared to downplay the role of mental health in mass tragedies.
"I'm really proud of the work we've done in this space, but we've had decades of neglect," he said on Monday.
"But respectfully, I will submit that regardless of the challenges it relates to behavioral health, there's not a country in the world that doesn't experience behavioral health issues," he added.
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