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As bullets flew inside Marjory Stoneman Douglas High School last week, killing 17 students, teachers and staff and leaving hundreds of others cowering in fear inside classrooms, Broward Sheriff Scott Israel says the armed and uniformed deputy on campus, Scot Peterson, failed to act.

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As people continue to mourn the deaths at Stoneman Douglas, Israel finds himself in a position to explain how one of his agency’s own might have failed them.

“Devastated,” he said. “Sick to my stomach. There are no words. These families lost their children. We lost kids, we lost coaches. There are no words.”

Israel said he reviewed surveillance video, witness statements and statements from Peterson.

“What I saw was a deputy arrive at the west side of building 12, take up a position and he never went in,” Israel said.

Israel said during the 6-minute attack Peterson might have used his radio but did little else.

“He remained outside for upwards of 4 minutes,” Israel said.

While suspected killer Nikolas Cruz fired round after round in the freshman building, during an attack that lasted about 6 minutes, Israel was clear on what Peterson should have done.

“Went in, addressed the killer. Killed the killer,” Israel said.

Israel said he planned to suspend Peterson without pay but Peterson quit.

There is an open internal affairs investigation into his actions that will continue even though Peterson quit.

Students are responding to news of Deputy Peterson’s inaction, too.

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Senior Nicholas Coke told CBS 4 News, “I’m disgusted by it. It’s in the job description to protect and serve and he did none of the above. It could have been prevented and knowing that he was at the entrance and did nothing, it baffles me.”

CBS4 News got a look at Peterson’s personnel file Thursday and also discovered that in 2014, according to the website for the Broward Crime Commission, Peterson won the SRO Officer of the Year award for Parkland.

The award stated, “…Deputy Peterson has proven to be reliable in handling issues with tact and judgment.” It also read, “Deputy Peterson is also active in mentoring and counseling students.”

A CBS4 News crew went to an address for Peterson in Palm Beach County on Thursday but sheriff’s deputies in that county stationed outside the home told us to leave.

BSO dropped another bombshell Thursday.

Since November 2008, BSO responded to 23 calls involving Nikolas Cruz or his family. Two of them stood out.

One from 2016 where BSO says they got information Cruz made a threat on Instagram to shoot up the school.

The other is from 2017 where an out of state caller said Cruz was “collecting guns and knives.”

The caller was concerned that Cruz “could be a school shooter in the making.” Israel said BSO placed the deputies who investigated those cases on restricted duty and opened investigations into how they handled those calls.

Those deputies are Edward Eason and Guntis Treijs.

“[We need to] take statements and make decisions about whether they should have done more or could have done more,” Israel said.

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The full press conference from Broward Sheriff’s Office headquarters can be seen below: