(NewsNation) — The image of a police officer with his hands on his face at the scene of the mass shooting in Highland Park, Illinois on Sunday highlights the strain that such mass-casualty events are taking on America’s police force.

“We can use all of the words that we possibly can, but that photo depicts exactly what first responders are feeling when they show up to the carnage,” said Kristen Zeeman, the former police chief of Aurora, Illinois, during an interview with NewsNation’s Adrienne Bankert on “Morning in America.”

Zeeman has personal experience with responding to these tragedies. Her former department was tasked with responding to a mass shooting in 2019 where six people, including the gunman, were killed in an act of workplace violence. She was also recently picked by the U.S. Department of Justice to be one of nine law enforcement experts who will be reviewing the police response to the mass shooting in Uvalde, Texas.

“This is happening over and over again…those first responders are hurting as is the community, and it is going to take a very long time, if ever — they’re forever changed. And I say that as someone who’s been through it,” Zeeman reflected.

There have been hundreds of mass shootings — defined as incidents where four or more people are shot — in 2022. Some of the most deadly incidents have occurred at events where there are mass gatherings of people.

“These mass gatherings are typically….very well secured by law enforcement. And I’m speaking on behalf of Aurora, because that’s what I know so well. But we have officers posted on roofs. We have officers posted behind the scenes, just in case,” Zeeman said. “And so for us it’s all about prevention. People, if you don’t notice us, that’s a really good day, but we’re always there and we’re always watching.”

She added that the prevalence of guns may make law enforcement’s jobs harder.

“A lot of people will agree that a lot of law enforcement leans maybe more conservatively and yet every police officer I talk to says, ‘Listen, we don’t want more guns because that means that we have to determine immediately, is someone a threat. Is that a good guy or a bad guy?'” Zeeman said. “And that puts officers in that position.”