SACRAMENTO (CBS13) — First responders rushed into chaos after Sunday’s mass shooting, not knowing if an active shooter was still on the scene.

“We were the first engine arriving,” said Capt. Eric Chase with the Sacramento Fire Department.

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Chase stepped off his fire engine and was surrounded by chaos.

“Mass panic, people running everywhere, as you can imagine,” Chase said. “People looking for cover, mourning with their family and friends that were down.”

There were bodies on the ground after a barrage of bullets left six dead and 12 injured. Firefighters typically have to wait for an all-clear from law enforcement, but Chase knew crews had to act fast.

“That was probably the biggest stress that I was dealing with in my own mind was, yeah, ‘Was more shooting going to happen?’ And not knowing who had been shooting or where that came from,” he said.

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Firefighters worked with police officers to treat the wounded not knowing what would happen next. Chief Gary Loesch defends the decision.

“It was a call that had to be made,” said Loesch. “We did what we had to do. We needed members to get in there and start life-saving measures on all the different victims that were there and get them transported to hospitals.”

In all, five trucks and ten medic units were called to save lives in one of the worst mass shootings in Sacramento history. Authorities recognized early that behavioral health teams were needed to counsel first responders.

“They are seeing things, victims down that are the age of some of their children or family members,” Chase said. “It hits them hard. They are human.”

Firefighters, like the community, are still trying to process what happened.

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“I’m going to say it hasn’t sunk in yet, honestly. I haven’t even been home yet. We’ll see,” said Chase.