First on CNN Business: Elizabeth Warren demands investigation into elite investors accessing Trump briefings

"Numerous investors may have used this early and insider information about the looming, tragic economic and public health consequences of the pandemic to extract profits for themselves," Warren wrote in the letter obtained first by CNN Business.

Warren, a Democrat from Massachusetts, urged the SEC and Commodity Futures Trading Commission to swiftly open an investigation into the episode.

The request follows a report by The New York Times alleging that senior members of President Donald Trump's economic team privately detailed concerns in late February about the looming pandemic. These warnings, reportedly relayed during private addresses to board members of the conservative Hoover Institution, contrasted sharply with the administration's public comments.

At the time, Trump was telling the public that the health crisis was "very much under control." The president even said in a tweet that the stock market was "starting to look very good to me!"

Word of those private concerns held by top US officials reportedly spread to elite investors through a hedge fund consultant, allowing these traders to make bets that stocks would drop.

According to the Times, the president's aides "appeared to be giving wealthy party donors an early warning of a potentially impactful contagion at a time when Mr. Trump was publicly insisting that the threat was nonexistent."

"Short everything" was the reaction of one major investor briefed on the memo from the hedge fund consultant, the Times said.

That proved to be a lucrative trade.

By March 11, the S&P 500 had plunged into the fastest bear market in US history. Retirement accounts and investment portfolios were crushed. Trillions of dollars of market value vanished.

In the letter, Warren said the incident "appears to be a textbook case of insider trading."

'Appalling abdication of duty'

Treasury Secretary Steven Mnuchin dismissed the Times report on Thursday as "another exaggeration" by the paper.

"I can't imagine this occurred," Mnuchin told CNBC. "By the way, there were plenty of investors who had their own views of what was going on at the time and were very concerned rightfully."

And the Times reported that legal experts say it is not apparent that any communications about these briefings violated securities laws.

But at least one billionaire investor expressed concern about the incident.

"But the problem is — and what crystalized that story — the feeling that the public was getting one set of briefings from White House spokesmen, 'Not to worry — it's mostly contained, or all contained' and then donors and insiders were getting a different set of more worrisome briefings inside the White House," hedge fund manager Jim Chanos told Hedgeye Risk Management on Thursday.

Warren urged the SEC and CFTC to review the material nonpublic information provided to investors and any trading that occurred as a result.

Specifically, Warren asked the regulators to determine which Trump administration officials provided the information, how that information differed from the public comments by the administration, who received the information and whether those individuals made trades of securities, futures, swaps or commodities.

"If this report is accurate, it represents an appalling abdication of duty by President Trump and top officials in his administration," Warren wrote.