Even though first responders train -- and train hard -- for all types of events, nothing can fully prepare them for the horrors of a mass shooting.
On Thursday, 25 first responders were recognized for exemplary service and a well-coordinated effort the night of the Lunar New Year shooting in Monterey Park.
But they said it's a bittersweet accomplishment, considering how common such incidents have become.
"The whole day, we were prepared for something to happen. But not this. Not this," said Jon Chang, a Monterey Park firefighter.
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As a Taiwanese American, Chang celebrates Lunar New Year, even though he was working that night, Jan. 21.
But then came the 911 calls.
Like all his colleagues, he had to snap into "auto-pilot," he says, and pushes emotions aside. He says you have to "get the job done, just like at any fire."
Only this time, it was the worst mass shooting in LA County history, and Chang could see that the victims were of Asian descent.
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"I can say that I still have two firefighters that are off. Because this incident…," said Chief Matthew Hallock, pausing. "I get emotional."
Hallock chokes up when he thinks about what his firefighters endured that night.
Twenty people were shot, and 10 died at the scene; 10 were seriously wounded, one dying later at the hospital.
"We didn't expect these things at the beginning of our careers, but here we are today," he said.
The chief spoke at a ceremony to recognize what went "right" that day.
Neighboring fire and police departments immediately jumped in to help. He's convinced their efforts saved lives.
But even as 25 LA area fire chiefs received their plaques, all of them are thinking about the next one.
Because what went wrong is that firefighters like Chang now have to live with what they witnessed, and so will their loved ones.
"My family, my wife. I lean on her a lot. She's my rock," he said.
Hallock says he even worries about how other mass shootings, like the one in Allen, Texas, can trigger trauma among his firefighters.
All the agencies offered peer counselors and access to mental health professionals, 24/7, to help them get through it.