Israel said he was "devastated, sick to his stomach" when he found out about Peterson's actions.
Israel told reporters Peterson should have "w$3 ent in".
Israel said the investigation remains ongoing.
The proposal to put guns in schools closely mirrors arguments pushed by the National Rifle Association, which staunchly opposes all gun control efforts.
On Thursday, in the NRA's first comments since the massacre, its head accused Democrats and media of "exploiting" the attack.
What did the officer do?
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And I want to represent our country well and I don't think there are a lot of people now in our government that do that". Speaking after her downhill race, she said: "I think the most important thing with social media is to be who you are".
However, Israel said video showed the deputy arriving at the west side of the building where the shooting took place.
"Schools need to be fortified", Israel said.
Deputies assigned to school campuses in south Florida's Broward County reportedly will now be allowed to carry rifles on school grounds.
Neither the deputy nor any representatives could immediately be reached for comment.
Scott Peterson resigned/retired after he was suspended without pay.
Major study backs efficacy of antidepressants
The FDA demands pharmaceutical companies provide data on all the clinical trials they sponsor-including unpublished trials. According to an estimation, nearly 350 million people have depression worldwide.
Media captionSeven things the NRA blames after Florida Why was he there?
He also spoke about Marjory Stoneman Douglas' School Resource Deputy on the day of the shooting. "They hate individual freedom".
"Somebody would say, 'He's on the second floor, ' and we had guys on the second floor saying, 'We're on the second floor, we don't see him.' That's when we figured out there's a tape delay", Pustizzi told the Sun Sentinel. "We give them a little bit of a bonus".
Galvano insisted the idea is not the same as arming teachers. No report was initiated, and the deputy later said he referred the call to the Palm Beach Sheriff's Office.
It was a markedly different tone than that deployed on stage minutes earlier by NRA Executive Vice President and CEO Wayne LaPierre, who delivered an unbowed defense of gun ownership and lashed out at Democrats - saying they are using the tragedy for "political gain".
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The official, who had direct knowledge of the matter, said GM had asked South Korea to inject funds into GM Korea through KDB. The union leader said in an interview that he believed in the possibility of GM leaving the country.