Sunday on CNN’s “Reliable Sources,” host Brian Stelter said President Donald Trump’s tweet saying the FBI missed the warning on Florida shooter because they are working on the Russia investigation was more evidence that “questions” about his fitness for office are so urgent.”

Stelter said Trump sounded “deeply trouble” and “unhinged.”

Very sad that the FBI missed all of the many signals sent out by the Florida school shooter. This is not acceptable. They are spending too much time trying to prove Russian collusion with the Trump campaign – there is no collusion. Get back to the basics and make us all proud! — Donald J. Trump (@realDonaldTrump) February 18, 2018

Stelter said “This has been a talking point from pro-Trump media ever since Friday that there is a link between the FBI’s failure and the ongoing Russia probes. This is nonsensical.”

He added, “Here are just some of the tweets from the president. You look at what he is doing here. He is undercutting his own national security adviser, he is ranting and raving about the fake media, he has got tweets riddled with misspellings and profanity. Maybe in person, President Trump is cool, calm, and collected. But on Twitter, he sounds deeply troubled. He sounds unhinged. This is why questions about his fitness for office are so urgent. This is the biggest story that I see happening right now.”

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