Washington (CNN) President Donald Trump said Friday that the armed school resource officer who stayed outside Marjory Stoneman Douglas High School as last week's shooting unfolded did a "poor job."

"When it came time to get in there and do something, he didn't have the courage or something happened, but he certainly did a poor job. There's no question about that," Trump said of Scot Peterson on the White House South Lawn before leaving to speak at CPAC.

"But that's a case where somebody was outside, they're trained, they didn't react properly under pressure or they were coward," Trump added. "It was a real shot to the police department."

Trump continued to criticize Peterson while speaking later Friday at the Conservative Political Action Conference.

"He didn't turn out to be too good, I'll tell you that. Turned out to be not good, not a credit to law enforcement, that I can tell you," he said.

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