It was a historic day on Wall Street. The Dow plunged 10% for its worst day since Black Monday in 1987. The 30-stock index fell 2,352 points — its largest point drop on record. Meanwhile the S&P 500 plunged 9% to close in bear market territory, thus officially ending the bull market that began in 2009 during the throes of the financial crisis. Here's what happened:

4:45 pm: A historic day on Wall Street

Thursday's market by the numbers: S&P 500 closed down -9.51% for its worst day since Oct. 19, 1987 when the S&P lost 20.47%. Hit a new 52-wk low back to Jan. 2019

Week-to-date: S&P is down 16.54% on pace for its worst week since Oct. 10, 2008

S&P is 26.9% below its intraday all-time high of 3,393.52 from Feb. 19

Dow closed down 9.99% for its worst day since Oct. 19, 1987 when the Dow lost 22.61% (Black Monday)

Dow closed down 2,352.60 points for its biggest point loss ever

NASDAQ closed down 9.43% for its worst day since Apr 14, 2000

Week-to-date: NASDAQ is down 16.02% on pace for its worst week since Sept. 21, 2001

NASDAQ is 26.8% from its intraday all-time high of 9,838.37 from Feb. 19

Russell 2K small caps closed down 11.18% for their worst day since Dec. 1, 2008 when the small caps lost -11.85%. Hit its lowest level back to July 2016

Week-to-date: Small caps are down 22.51% on pace for their worst week ever back through 1987

11 out of 11 sectors were negative today led by Energy down 12.3% for its worst day since Mar. 9th

4:29 pm: Nasdaq suffers worst day since the tech bubble

The Nasdaq Composite tanked 9.4% Thursday, its biggest drop since April 2000 before the burst of the dot-com bubble. Liberty TripAdvisor, Full House Resorts and Eldorado Resorts were among the biggest losers in the tech-heavy index, falling more than 35% each. The so-called FANG stocks including Netflix, Facebook and Google-parent company Alphabet all plunged more than 8% Thursday. - Li

4:08 pm: Bull market officially dead

With Thursday's historic plunge, the record-long stock market bull run has officially ended. The S&P 500 tanked 9.5%, falling into bear market territory, or more than 20% from its recent peak. The Dow also suffered its worst point drop ever and the biggest percentage decline since 1987. - Li

4:01 pm: One hint of green

Occidental Petroleum was the only stock in the S&P 500 to close in positive territory as the broader index fell 9.5% to join Dow Jones Industrial Average in bear market territory. Occidental Petroleum gained .09% to close at $11.89. On Wednesday the stock dropped 17% after the company slashed its dividend, and shares are down 72% over the last month. - Stankiewicz

4:00 pm: Dow drops the most since 1987 crash, S&P sinks into bear market

Stock losses accelerated into the close as stocks plummeted to their lowest levels in the final minute of trading. The Dow tanked 2,352 points for a 10% drop, its largest single day decline since the Oct. 1987 crash. The S&P 500 dropped 9.5%, closing in bear market territory, or more than 20% below its recent high. The Nasdaq dropped 9.4%. - Stevens, Li

3:46 pm: Treasury yields rise, but bond selling may herald investor stress

Rising Treasury yields typically mean investors are ditching the security of bonds because of an improving economic outlook or in anticipation of more inflation, causing bond prices to dip and yields to rise. The opposite has been true for most of this coronavirus market rout with bond yields collapsing as fears of a global recession send investors crowding into the safety of bonds. But something odd is happening now. 10-year and 30-year Treasuries are falling in value amid the Dow's worst day since 1987. This may hint at something more insidious, some traders said. If equity losses accelerate to the point where investors start to worry about the health of their firms, they often are forced to sell safe U.S. debt in the hopes of stockpiling cash. That selling drives up rates. The spike in long-term rates means "the market is liquidating and we know the market is liquidating equities," said Ian Lyngen, head of rates strategy at BMO Capital Markets. "The fact it is now liquidating longer dated Treasurys suggests the rush to go to cash is significant and it is the type of liquidity problem were the Fed needs to be more aggressive." — Franck, Domm

3:36 pm: Sector snapshot: 9 out of 11 S&P 500 sectors currently in bear market territory

There are now nine S&P 500 sectors trading in bear market territory, or more than 20% below recent highs. Energy is by far the biggest laggard, trading 51% below its 52-week high. The financials sector is the second worst performer, down 33% from its high. The two sectors not in a bear market are health care and staples, but each is 18% below its high, putting both in correction territory and on the cusp of a bear market. - Stevens

3:13 pm: 'Fear Gauge' surges past 70

The Cboe Volatility Index rose more than 18 points to break above 70 on Thursday, its highest level since the financial crisis, as the wild stretch of trading continues. The index, often called Wall Street's "fear gauge," measures the potential future moves of the S&P 500 implied by the options market. The VIX spent most of 2019 below 20. — Pound

2:50 pm: RBC slashes S&P 500 forecast, upgrades health care sector

RBC Capital markets just slashed its S&P 500 year-end price target to 3,279 from 3,460, representing a 1.5% gain on the index in 2020. ""Embedded in our new target is the idea that the brunt of the pain that the US equity market will experience due to the coronavirus will occur early in the year, with the bulk of the economic impact coming mid year, and a recovery trade taking hold once the news flow around the coronavirus improves," said the firm's head of U.S. equity strategy Lori Calvasina. RBC also upgraded the health care sector to overweight from market weight, given the group of stocks "continues to look deeply undervalued relative to the S&P 500." – Fitzgerald

2:27 pm: Dow back down 2,000

The Dow is now back down 2,000 points, after a brief respite on the Fed's funding actions. Traders remained jittery about the spreading coronavirus. In the latest, New York Gov. Andrew Cuomo announced a ban on gatherings of 500 or more people as public officials try to contain the outbreak.— Li

1:30 pm: Senate cancels recess, prioritizing coronavirus response

The Senate will cancel its recess planned for next week as Congress tries to pass a plan to respond to the effects of the coronavirus outbreak, Majority Leader Mitch McConnell said Thursday. "Notwithstanding the scheduled state work period, the Senate will be in session next week," the Kentucky Republican said in a tweet. "I am glad talks are ongoing between the Administration and Speaker Pelosi. I hope Congress can pass bipartisan legislation to continue combating the coronavirus and keep our economy strong." — Fitzgerald

1:25 pm: Cuban buys Twitter, says market 'shouldn't get too excited'

Billionaire Mark Cuban said on CNBC's "Halftime Report" that he bought shares in Twitter on Thursday even though he is unsure when the market will start to bounce back. He said investors should keep in mind the rally that stocks have been on over the past year. "In reality, we're just back where we were 13 months ago," Cuban said. "We didn't get upset or excited when it went up fast, and we shouldn't get excited when it goes down fast. We haven't hit a level that is really out of line." — Pound

1:08 pm: Regional banks cut losses

The SPDR S&P Regional Banking ETF (KRE) is close to wiping out losses in heavy trade after the Fed announces new funding actions. KRE was last down 0.4% -- Francolla

12:55 pm: Stocks pare losses on Fed action

Stocks cut losses after the New York Fed said it will conduct purchases across a range of maturities. It will offer $500 billion in a three-month repo operation at 1:30 pm ET. The Fed is also expanding Treasury purchases beyond bills. "Specifically, the Desk plans to distribute reserve management purchases across eleven sectors, including nominal coupons, bills, Treasury Inflation-Protected Securities, and Floating Rate Notes," it said. The Dow was down about 1,200 points after plunging more than 2,200 points at its low. — Li

12:43 pm: European stocks suffer worst one-day drop ever

The pan-European Stoxx 600 plummeted 11% Thursday, posting its worst one-day drop in history. The plunge came after the European Central Bank decided Thursday not to cut interest rates, disappointing investors who were expecting a reduction in borrowing cost. Meanwhile, Trump said the U.S. will suspend all travel from most of Europe for 30 days to curb the spread of coronavirus. -- Li

12:23 pm: Dow on track for worst one-day decline since 1987 crash

The Dow is now down more than 9%, putting it on pace for its largest one-day decline since the 1987 crash. - Stevens

11:52 am: Dow drops to session low, down more than 2,200 points

Losses accelerated in late morning trading with the Dow dropping to a new session low, down more than 2,200 points for a loss of more than 9%. The S&P 500 and Nasdaq are each down more than 8%. - Stevens

11:39 am: Former Goldman boss says US needs to go 'all-in' to combat coronavirus

Former Goldman Sachs CEO Lloyd Blankfein, who knows a little something about risk management after navigating that institution through the financial crisis, had some advice on what the U.S. government should do now to combat the coronavirus pandemic. "Good risk management: at this point, go all-in on social separation, and all-in on financial relief to those most economically vulnerable (individuals and sm biz)," Blankfein said in a tweet. "Save the second guessing for later. I would welcome if we look back 3 months from now and think we over-reacted." - Melloy Tweet

11:31 am: Trump says markets are going to be 'just fine' as stocks crater amid coronavirus worry

President Donald Trump said that markets will be "just fine" Thursday, as stocks sold off in yet another dramatic session fueled by worries over the coronavirus outbreak and the administration's response to it. Trump's remarks Thursday came as he met with Leo Vardakar, the taoiseach of Ireland. At Capitol Hill, lawmakers were battling over what steps to take next to combat the rapidly spreading and deadly disease. House Republicans made it clear that they won't support the new emergency aid bill unveiled by Democrats, at least not in its current form. – Calia, Breuninger

11:30 am: Lagarde: Central banks shouldn't be 'line of first response'

European Central Bank President Christine Lagarde called the coronavirus "a major shock" to the global economy and called upon fiscal authorities to help combat the pandemic. For its part, the ECB on Thursday announced more stimulus but held its policy rate at current levels. Lagarde sad officials chose not to cut rates as they consider asset purchases and increased lending efforts to be "the most efficient response" to the current crisis. She also said the world shouldn't be looking to central banks to lead the way. "I don't think anybody should expect any central bank to be the line of first response. It's fiscal first and foremost," she said in a news conference after the bank met. – Cox

11:17 am: Energy, financials lead declines

All 11 S&P 500 sectors are sharply lower, with energy and financials leading the declines, down 9.9% and 8.8%, respectively. The utilities, materials, discretionary and industrials sectors are all down more than 8%. The relative outperformer is health care, which is only down 5.8%. – Stevens

10:52 am: More than 320 S&P 500 stocks sink to at least one-year lows

A little more than an hour into trading, and 324 S&P 500 components have already fallen to their lowest level in at least a year. The names include Facebook, Best Buy, Chipotle, Colgate and Tyson Foods. - Hayes, Stevens

10:44 am: Jim Cramer believes White House debating big plans to ease markets

Shortly after trading was halted around 9:38 a.m. ET, CNBC's Jim Cramer took a phone call live on television on "Squawk on the Street." After the call, he said he believes the government is debating some big options to tackle the economic and financial markets crisis arising from the coronavirus pandemic."I think that's about to change," Cramer said about the uncertainty over what further actions the Trump administration may take to deal with the coronavirus fallout. "I do believe that they'll enact some of the ideas I just talked about earlier." – Li, Belvedere

10:29 am: NYSE decliners lead advancers 73-1

About 73 stocks at the New York Stock Exchange fell for every one advancer as global markets got roiled by worries over slower economic growth due to the coronavirus spread. About 2,940 stocks traded lower while just over 40 advanced. - Imbert

10:25 am: European stocks extend losses, on track for worst day ever

As global markets fall, the Euro STOXX 600 is down 9.15%, putting it on track for its worst day ever. For the week it's currently down 18%, on track for its steepest weekly loss since Oct. 2008. - Francolla, Stevens

10:21 am: Dow on pace for largest weekly point loss in history

The Dow has lost 4,300 points so far this week, and is on pace for its worst weekly point loss ever. It is not, however, the 30-stock index's worst week in terms of a percentage drop. So far it's down 15.9% on the week, which puts it on track for its steepest weekly loss since Oct. 2008. - Francolla, Stevens

10:05 am: Calls of the day

There were a ton of stock calls on Thursday as analysts try to pick winners and losers amid crisis. JPMorgan downgraded Boeing to neutral from overweight.

Deutsche Bank upgraded Snap to buy from hold.

Morgan Stanley lowered its price target on Tesla to $480 from $500.

BMO downgraded Hilton to market perform from outperform.

Argus downgraded MGM to hold from buy.

JPMorgan upgraded HP to overweight from neutral.

Morgan Stanley upgraded Tencent Music Entertainment to overweight from equal weight.

RBC upgraded Anheuser-Busch InBev to outperform from sector perform.

Bank of America downgraded Toll Brothers & Lennar to underperform from neutral CNBC Pro subscribers can read more here. — Bloom

9:59 am: VIX surges to 65

The Cboe Volatility Index, a measure of the 30-day implied volatility of the S&P 500 known as the "VIX" or the "fear gauge," popped to 65.6 in morning trading Thursday. This level was only last seen at the height of the financial crisis more than a decade ago. -- Li

9:53 am: No S&P 500 stock in the green

None of the stocks in the S&P 500 were above Wednesday's closing price when trading was halted at 9:35 a.m., according to FactSet. The biggest decliners were Royal Caribbean at -24.3%, Norwegian Cruise Lines at -20.4%, and Live Nation at -17.5%. — Pound

9:50 am: Trading resumes

The market reopened after a 15-minute halt. The S&P 500 added to its losses, now down 7.4%.— Li

9:35 am: Trading halted for 15 minutes

The level-one circuit breaker was triggered minutes into the opening bell after the S&P 500 dropped 7%. Trading is halted for 15 minutes until 9:50 am ET. — Li

9:31 am: S&P 500 opens down 6.6%, Dow plunges 1,700 points

The stock rout deepened on Thursday with the S&P 500 opening the session off 6.6%, joining the Dow in bear market territory. The 30-stock benchmark plunged 1,700 points at the open, while the Nasdaq tanked 6.9%. A key market-wide circuit breaker will trip once the S&P 500 falls 7%. — Li

9:14 am: S&P 500 ETF now down 7%

The SPDR S&P 500 ETF Trust (SPY), which tracks the S&P 500, is still trading in premarket, while futures on the Dow, the S&P 500 and Nasdaq-100 all traded at the so-called limit down threshold, off by 5%. The SPY is now down 7%. If the S&P 500 tanks the same amount when the markets open, a key "circuit breaker" will be triggered, resulting in a 15-minute halt in trading. — Li

9:04 am: Carnival shares fall further after trading re-starts

Shares of Carnival fell to more than 21% below Wednesday's closing price in premarket trading after announcing that its Princess Cruise Lines would pause its shipping operations for 60 days. Trading was halted shortly before the announcement. There have been confirmed cases of the coronavirus on multiple Princess ships. — Pound

8:58 am: ECB leaves interest rates unchanged, disappointing traders

The European Central Bank kept interest rates unchanged in its policy decision Thursday, despite market expectations for a reduction amid the coronavirus outbreak. The central bank did announce measures to support bank lending, and expanded its quantitative easing (QE) program by 120 billion euros ($135.28 billion). – Li

8:56 am: ETFs that track the S&P 500, Nasdaq-100 point to steeper losses

The SPDR S&P 500 Trust ETF SPY, which tracks the S&P 500 index and continues trading even if futures are halted, is now down more than 6.6%. The Invesco QQQ, which tracks the Nasdaq-100, is down more than 6.2%. This suggests that the Street is in for steeper losses than the 5% drop futures registered before reaching the so-called limit-down level. - Stevens

8:50 am: Dow's roller-coaster ride

On Wednesday the Dow closed 1,464 points lower. It was the 30-stock index's seventh 1,000-plus point swing in either direction over the last 13 trading sessions. - Stevens, Rattner

8:41 am: Nike shares tank after footwear imports from China plunge

U.S. footwear imports from China just had their worst January in more than a decade as the industry suffered the double whammy from the trade war and the coronavirus outbreak. China is the biggest manufacturer of footwear in the U.S, as 70% of shoes sold here come from the developing country. Shares of Nike tanked 8.5% in premarket trading, set to extend a massive sell-off this year that's seen the stock plunge 17%. - Li

8:40 am: Less than an hour before the open, here's where we stand

Stocks are set to plummet when the market opens in less than an hour. Earlier futures on the Dow, S&P 500 and Nasdaq-100 all dropped below 5%, which is the so-called limit down threshold. Once futures fall that much, exchanges halt trading of futures contracts, which acts as a floor for selling until regular trading resumes at the opening bell at 9:30 a.m. The SPDR S&P 500 Trust ETF (SPY), which tracks the S&P 500 index and continues trading even if futures are halted, is down 5.2%. - Stevens

8:26 am: Carnival Corp. halted due to news pending

Shares of cruise operator Carnival Corp. were halted for trading due to news pending. Earlier in premarket trading the stock dropped more than 15% as the coronavirus outbreak continues to hit the travel industry. The CDC has warned that those at higher risk, including older adults, should avoid cruise travel. Shares of carnival have lost more than half their value in the last month, falling just over 50%. - Stevens

8:21 am: El-Erian says stock market decline will reach 30% from highs, sees a recession on the horizon

The U.S. stock market will drop as much as 30% from last month's highs as global economies go into coronavirus-driven recessions, said Mohamed El-Erian, the chief economic advisor at Allianz, who correctly predicted earlier in the week the selling would continue until a bear market was reached. The former CEO of investment powerhouse Pimco said on CNBC's "Squawk Box" on Thursday that investors should not expect a quick recovery in stocks when a bottom is finally reached. "We are going into a global recession. We are going to see a spread of economic sudden stops," El-Erian said. "The trouble with economic sudden stops is it's not easy to restart an economy. You've got to get people to re-engage. You've got to coordinate the restart. The economic damage is going to last." - Stankiewicz

8:16 am: ETF that tracks the S&P 500 sheds 5.2% in premarket trading

The SPDR S&P 500 Trust ETF (SPY), which tracks the S&P 500, is down 5.2% during Thursday's premarket trading as the sell-off intensifies. The S&P 500 is on track to enter a bear market when trading begins. - Stevens

8:09 am: Boeing beating continues as futures point to 14.5% drop after Wednesday's 18% plummet

Industrials crown jewel Boeing was on track Thursday morning to open more than 14% below where it closed on Wednesday, adding to its whopping 49% decline over the last six months. Boeing equity on Wednesday suffered its worst day on Wall Street since 1974 — an 18% plunge — after the planemaker said it was immediately suspending hiring and imposing measures to conserve cash.The company, already grappling with the fallout of two fatal crashes of its 737 Max craft, came under additional pressure over night after President Donald Trump said the U.S. will ban travelers from Europe for 30 days starting on Friday in an effort to curb the spread of the novel coronavirus. — Franck

8:07 am: The market may trigger a 'circuit breaker' for a second time this week

The brutal sell-off in the futures market Thursday signaled a so-called circuit breaker could be triggered when the markets open. A market trading halt may occur at "three circuit breaker thresholds" on the S&P 500 due to large declines and volatility, which helps keep stocks from a free fall. If the S&P 500 drops 7%, trading will pause for 15 minutes. Just on Monday, trading was halted temporarily minutes into the opening bell. The S&P 500 ended up suffering its worst day since the financial crisis at the beginning of the week. - Li

7:55 am: Airline stocks sink as Trump institutes travel ban

Airline stocks were under pressure in Thursday's premarket trading after President Trump imposed a 30-day ban on foreigners arriving from most of Europe. American Airlines and United Airlines were both down more than 15%, while Delta Air Lines slid 13%. Travel stocks have gotten slammed as the coronavirus outbreak has hit demand. – Stevens

7:45 am: CME Group to close Chicago trading floor as a precaution due to coronavirus

CME Group announced Wednesday night it will close its Chicago trading floor in a precautionary move due to the coronavirus pandemic. The closing will take effect Friday "at the close of business," CME said in a statement, noting that no coronavirus cases have been reported at the Chicago Board of Trade trading floor. This would make CME the first major U.S. exchange to close a trading floor due to concerns over the coronavirus. – Fitzgerald

7:43 am: S&P 500 poised to join Dow in bear market territory as futures hint at 4.7% slide

Futures contracts tied to the S&P 500 showed that the major market index is on track to join the Dow in bear market territory at the opening of trade on Thursday. Though an official bear market is determined on a closing basis, the S&P 500 is on track to slide 4.7% based on premarket futures trading. That would put the index 22.88% below its record close of 3,386.15 hit on Feb. 19. The Dow, meanwhile, is poised to fall further into a bear market one day after its historic, 11-year bull market run came to an end on Wednesday. Futures showed the blue-chip index on track to dive 1,200 points, or 5%, at the opening bell. — Franck

7:40 am: Trump addresses the nation on Wednesday night

President Donald Trump gave a speech on Wednesday evening, announcing a ban on travelers to the United States from Europe, in an attempt to stem the spread of the coronavirus pandemic. The ban is in place for the next 30 days. Trump also announced that he would ask Congress for legislative action to provide payroll tax relief, as well as other measures for several groups impacted by the virus. In addition to legislation, Trump said he would instruct the Small Business Administration to "provide capital and liquidity" to small businesses. - Fitzgerald

7:36 am: Tom Hanks and Rita Wilson test positive for coronavirus

Academy Award-winning actor Tom Hanks and his wife Rita Wilson have tested positive for the coronavirus, Hanks said Wednesday. "Hello, folks. Rita and I are down here in Australia," he wrote. "We felt a bit tired, like we had colds, and some body aches. Rita had some chills that came and went. Slight fevers too. To play things right, as is needed in the world right now, we were tested for the Coronavirus, and were found to be positive." Hanks and Wilson are in Australia for the pre-production of a Warner Bros. film. – Fitzgerald

7:35 am: Trump speech disappoints markets

Investors were left wanting more robust fiscal stimulus measures after President Donald Trump's speech Wednesday night. Trump said the administration would provide financial relief for workers who are ill, caring for others due to the virus or are quarantined. But Tom Essaye, founder of The Sevens Report, said none of the measures announced "are a silver bullet for coronavirus, and as such the market is reacting with short term disappointment." Ernie Tedeschi of Evercore ISI said Trump didn't "offer up major new ideas on stimulus and only said he'd propose a vague payroll tax holiday to Congress without strongly standing up for any firm size/magnitude." —Imbert

7:32 am: NBA suspends season due to coronavirus

The National Basketball Association on Wednesday night suspended its season indefinitely after a Utah Jazz player tested positive for the new coronavirus. "The NBA is suspending game play following the conclusion of [Wednesday night's] schedule of games until further notice," the league said in a statement. "The NBA will use this hiatus to determine next steps for moving forward in regard to the coronavirus pandemic." The National Hockey League said that it is "continuing to consult with medical experts and is evaluating the options" for its ongoing season. – Fitzgerald

7:05 am: Stock futures tank, Dow set to fall 1,100 points