SAN BERNARDINO ( — “It was something that, although we train for it, it’s something that you’re never actually prepared for,” said a lieutenant who responded to Wednesday’s mass shooting in San Bernardino.

Lt. Mike Madden of the San Bernardino Police Department was less than a mile away from the Inland Regional Center when he received a call via dispatch of an active shooter incident. Before arriving on scene, he said he could tell by the voice of the dispatcher something horrible had happened.

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“This was actually happening. This was a real event and it was the event that, you know, we have an active shooter. We have an active shooter going on in our city,” he said.

The shooting unfolded just before 11 a.m. at the center in the 1300 block of S. Waterman Avenue.

“I realized as I was getting closer that I was one of the very first units sent there,” said Madden, who arrived almost simultaneously to the scene with another unit and called for additional officers.

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“My goal was to assemble an entry team and enter into the building to engage the active shooter,” he said. “This mindset and this type of training became indoctrinated in us after the Columbine shooting.”

Madden says it took about two minutes from that point to have a team assembled.

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He and three other officers made first entry into the building. Though they trained for this type of situation, he says nothing could have prepared them for what they encountered once inside the conference room.

“The situation was surreal,” he said. “It was unspeakable the carnage that we were seeing. The number of people that were injured and unfortunately already dead.”

Madden said the initial 50 people he encountered did not want to come to officers and were fearful.

“We had to tell them several times, ‘Come to us. Come to us.’ And ultimately they did. Once that first person took the motion forward, it opened the floodgates,” he recalls. He also described the chaotic scene as “loud.”

“The fire alarms were going off. There were people who were obviously injured and obviously in great amounts of pain and that was evident in the moans and wails that we were hearing in the room,” he said. “It was very loud in the room and we also had fire sprinklers going off.”

In all, 14 people were killed in Wednesday’s massacre. Twenty-two people were reported injured. Several of the injured victims remain at Loma Linda University Medical Center, some of which were in serious condition.

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“This was tragedy that I’ve never experienced in my career and that I don’t think most officers do,” Madden said.