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President Donald Trump excoriated an NBC News correspondent as a “terrible reporter” on Friday after he asked the president to calm Americans who were scared because of the coronavirus pandemic.

Trump’s latest personal broadside on the media came at a news briefing in which he appeared to minimize the fears of the American public by saying there was cause for optimism about drug therapies for coronavirus — treatments that one of his top government scientists had said were not at all proven.

At the Trump administration's coronavirus task force's daily briefing, Trump’s director of the National Institute of Allergy and Infectious Diseases, Dr. Anthony Fauci, made clear that any evidence about drug therapies being tested at the moment was strictly “anecdotal” and not the product of a “clinical trial.”

“You really can’t make any definitive statement about it,” Fauci said.

Moments earlier, Fauci was asked whether there was any evidence that one such drug— hydroxychloroquine — might be used as an effective prophylactic measure against coronavirus.

"The answer is no," Fauci replied.

Trump nevertheless said that he felt "good" about the treatments and that the federal government had already ordered "millions of units" of them.

NBC News’ Peter Alexander, a White House correspondent and a weekend anchor of "TODAY," then asked Trump whether his “positive spin” regarding the potential treatments was giving Americans false hope.

“Is it possible that your impulse to put a positive spin on things may be giving Americans a false sense of hope?” Alexander asked.

“No, I don’t think so,” Trump replied.

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“It may work, it may not work, Trump said. “I feel good about. That’s all it is, it’s a feeling.”

Alexander responded by asking Trump to talk directly to Americans who are scared by the pandemic, which triggered the president to reply with an insult.

"What do you say to Americans who are scared though? I guess, nearly 200 dead, 14,000 who are sick, millions, as you witnessed, who are scared right now," Alexander asked. "What do you say to Americans who are watching you right now who are scared?"

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“I say that you’re a terrible reporter,” Trump said. “That’s what I say. I think that’s a very nasty question.”

"The American people are looking for answers and they’re looking for hope, and you’re doing sensationalism," Trump said.

"Let’s see if it works," the president added about possible treatments. "It might and it might not. I happen to feel good about it, but who knows, I’ve been right a lot. Let’s see what happens," he added.

NBC News Chairman Andy Lack defended Alexander.

“Peter Alexander is an outstanding reporter. His line of questioning at today’s White House briefing was fair, straightforward, and necessary," he said in a statement Friday.

U.S. stocks, which had been up for the day before Trump began the news conference, tumbled steadily as the president spoke. In recent trading, the Dow Jones Industrial Average was down nearly 200 points, or about 1 percent.

Trump returned to the topic of media coverage later in the news conference, using another question from another reporter to levy an additional attack on Alexander.

Trump was asked if he felt "going off on Peter" was "appropriate when the country is going through something like this"

"I do," Trump replied.

"I’ve dealt with Peter for a long time," Trump said. "And I think Peter is not a good journalist."

Later in the briefing, Vice President Mike Pence responded to Alexander's initial question, saying, “do not be afraid, be vigilant” and went on to explain that the risk of serious illness for most Americans is low.

Alexander discussed the exchange with MSNBC's Andrea Mitchell hours later, saying that the question he posed Trump was a "softball" that was designed to allow the president to "reassure" scared Americans.

"I’m sure there are plenty of baseball fans watching out there now. In TV terms, we call this a softball," Alexander said. "I was trying to provide the president an opportunity to reassure the millions of Americans, members of my own family and my neighbors and my community and plenty of people sitting at home right now. This was his opportunity to do that, to provide a sort of positive or uplifting message."