Stocks tanked on Monday, triggering a key market-wide "circuit breaker" designed to prevent the market from falling through the floor.

The S&P 500 plunged about 8% right after the opening bell, tripping the level one circuit breaker that resulted in a trading halt for 15 minutes. The Dow Jones Industrial Average plummeted 2,250 points at the open. The market reopened at 9:46 a.m. ET.

Stocks ended up closing at their session lows after President Donald Trump said in a press conference that the worst of coronavirus could last until August and the U.S. "may be" headed into a recession. The Dow plummets 2,997 points, suffering its worst day since the "Black Monday" market crash in 1987. The S&P 500 ended the session down nearly 12%.

Monday's brutal sell-off came even after the Federal Reserve cut interest rates to near zero in an aggressive bid to save the U.S. economy from the coronavirus fallout.

The circuit breaker has kicked in three times in the past week as investors exited the market with the coronavirus outbreak disrupting global supply chains and fueling fears of a recession. The stock market has tumbled into a bear market, or down more than 20% from their recent highs.