Stocks plummeted on global-growth fears for a second straight day Friday in a plunge that dragged the Dow industrials into correction territory. 
 
 The global market rout pummeled stocks and commodities as fresh evidence emerged that China’s economy is slowing, spooking investors. 
 
 The Dow industrials lost 530.94 points, or 3.1%, to close at 16459.75, putting it in correction territory, as defined by a 10% decline from a recent high. The S&P 500 dropped 64.84 points, or 3.2%, to close at 1970.89. The Nasdaq Composite fell 3.5%, or 171.45 points, to 4706.04. 
 
 The Dow’s more than 1,000-point drop this week was the largest weekly drop since the week ended Oct. 10, 2008. 
 
 Related Video U.S. stocks tumbled on Friday as the Dow industrials plunged 531 points, dragging the index into correction territory. WSJ's Geoff Rogow and Barron's Jack Hough discuss what's spooking investors and the outlook for global markets in the week ahead. Photo: Getty 
 
 U.S. oil prices also briefly dropped below $40 a barrel on Friday, a level not seen since the financial crisis. 
 
 Signs of a sharp slowdown in the world’s second-largest economy have unnerved investors since Beijing surprised markets last week by devaluing its currency. Shares in the U.S., Asia and Europe have tumbled, along with commodity prices as investors fretted about waning Chinese demand just as supplies are surging. 
 
 The market turmoil has some traders exercising caution. 
 
 “You have a situation that’s tough to play,” said Christopher Cady, a New York-based trader. He said he closed out bets toward the end of the week that U.S. stocks would fall. “Nimble…is the new black.” 
 
 The pan-European Stoxx Europe 600 ended the session 3.3% lower, closing out its biggest week of losses since August 2011. The index has now lost nearly 13% since its April peak, entering correction territory. 
 
 Earlier, the Shanghai Composite Index tumbled 4.3%, hitting its lowest level since March, despite Beijing’s efforts to prop up the market in recent weeks. In Japan, the Nikkei fell 3% to a six-week low. 
 
 An early gauge of China’s factory activity fell to a six-and-a-half year low in August, heaping further pressure on stocks and commodities after Thursday’s global selloff. 
 
 “Now we’ve had some harder evidence that China is slowing relatively fast, people have chosen to get out,” said Kiran Ganesh, a multiasset strategist at UBS Wealth Management, which oversees around $2 trillion of assets. 
 
 A surge in investor demand for assets considered safest during times of market stress sent the yield on 10-year U.S. Treasury bonds to 2.042%, its lowest level since April. Yields fall as bond prices rise. 
 
 The dollar fell by around 1% against the euro and Japan’s yen. The euro and yen have recently tended to rise during times of market stress. 
 
 Some investors and analysts say they think the tumult in the markets could complicate the Federal Reserve’s plans to raise interest rates. 
 
 “The Chinese have created an air of fragility around the globe. Markets will now surely have to firm up considerably for the Fed to pull the trigger next month,” said Deutsche Bank analyst Jim Reid. 
 
 Ultralow interest rates have fueled a big rally in stock markets since the financial crisis. On Wednesday, minutes of the Fed’s latest policy meeting showed officials were divided over when to raise rates, with some citing concerns over China’s economy as a reason to hold back. 
 
 But a delay in lifting rates may bring little comfort to investors if slowing global growth is underpinning the Fed’s caution. 
 
 Paul O’Connor, a senior fund manager at Henderson Global Investors, which manages £82 billion ($129 billion) in assets, said he has been selling stocks and buying bonds in recent months, fearing further spillover from the recent Chinese selloff. 
 
 “Is there a buying opportunity in stuff that has got beaten up, or will it start to erode confidence in developed market assets? We’re in the latter camp,” he said. 
 
 Global equities suffered $8.3 billion of outflows in the week ended Thursday, representing the worst week in almost four months, according to data from Bank of America Merrill Lynch published Friday. Losses were particularly heavy in the emerging markets and the U.S. 
 
 The recent rout in commodity markets continued Friday as fears over waning Chinese demand intensified. 
 
 Oil prices extended their recent declines. Brent crude oil, the global benchmark, fell 2.5% to around $45.48 a barrel, its lowest level since January. The U.S. benchmark settled down 2.1% at $40.45 a barrel. 
 
 Industrial metals prices also fell as the Chinese data reignited worries about the future pace of demand from the world’s top consumer. 
 
 “Commodity markets are telling us this is quite serious,” said Neil Dwane, head of European equities at Allianz Global Investors, which oversees EUR412 billion ($463 billion) of assets. 
 
 --Chiara Albanese, Christopher Whittall, Josie Cox and Ese Erheriene contributed to this article. 
 
 Write to Leslie Josephs at leslie.josephs@wsj.com and Tommy Stubbington at tommy.stubbington@wsj.com ||||| Wall Street suffered one of its most volatile sessions in years Monday, with the Dow industrials plunging more than 1,000 points in the opening minutes, bouncing back to recover most of the losses and then fading into the final bell to record the biggest drop in four years. 
 
 Meanwhile the main benchmark S&P 500 slipped into correction territory, having fallen more than 10% from its peak reached on May 21. 
 
 “Short-term fear of the unknown is still in the driver’s seat, I would expect more volatility in the coming weeks,” said Kate Warne, investment strategist at Edward Jones. 
 
 Indeed, Monday’s trading session saw the main indexes plunge by more than 5%. Nearly 14 billion shares changed hands on Monday, the largest volume since August 10, 2011. 
 
 Investors remained concerned about global growth in the face of plummeting commodity prices and slowing growth in China, the second largest economy in the world. 
 
 The Dow Jones Industrial Average DJIA, +0.75% ended the day down 588.47 points, or 3.6%, at 15,871.28—its lowest settlement since February 2014. All 30 members of the Dow finished the day in negative territory. 
 
 The S&P 500 SPX, +0.85% dropped 77.68 points, or 3.9%, to 1,893.21, the lowest level since October 2014. The index is down 8% year to date. Nearly all 500 members of the index closed with a loss. 
 
 Both the Dow and the S&P 500 scored their biggest one-day percentage declines since August 2011. 
 
 The Nasdaq Composite COMP, +1.29% ended the day down 179.79 points, or 3.8% at 4,526.25. 
 
 “Trading volumes are driven by ETFs today, but we are not seeing a lot of panic, where people dump large amounts of stocks in one go. There are still buyers out there, who are picking up stocks that have seen large corrections. However, volatility is back, so seeing large intraday and day-to-day swings is not surprising,” said Brian Fenske, head of sales trading at ITG. 
 
 Sal Arnuk, co-head of equity trading at Themis Trading, described Monday’s open as painful. “There’s definitely blood on the street. You can check the level of the VIX,” Arnuk said. 
 
 Implied volatility on the S&P 500, as measured by the CBOE Volatility Index VIX, -7.78% jumped to 38, significantly above the long-term average of 20. Investors piled into Treasurys, briefly pushing the yield on the 10-year note below 2%. Bond yields move inversely to prices. 
 
 Many investors expected the People’s Bank of China to take some action over the weekend to support the financial system. In the absence of any move, a brutal bout of selling overtook markets. The Shanghai Composite Index SHCOMP, +0.39% closed down 8.5%. 
 
 Read: Investors haven’t been this terrified since 2009 
 
 Ric Edelman, chief executive officer and chairman of Edelman Financial Services, said that his firm hasn't experienced a barrage of calls from panicky clients. 
 
 “It appears that most of the selling is done by algorithms and institutional investors rather than retail investors. We think that’s because retail investors have learned their lesson of 2008: that the best thing to do at a time like this is nothing,” Edelman said. 
 
 Stocks to Watch: Shares of Apple Inc. AAPL, +3.31% switched between big losses and big gains. Share closed down 2.5%, after opening down more than 4.3%. The stock entered bear-market territory on Friday. 
 
 Energy stocks suffered as the U.S. crude benchmark CLV5, +0.00% struggled to hold above $38 a barrel. 
 
 But AGL Resources Inc. US:GAS soared 28% after the energy company received a $12 billion buyout bid from Southern Company. SO, -0.96% 
 
 Read more in Movers & Shakers. 
 
 NIK, +0.97% Other markets: In addition to the Shanghai Composite’s heavy losses, the Nikkei 225 index NIK, +0.97% slid 4.6%, pressured by a strong Japanese yen. Investors flocked to the perceived safe haven of the yen, pushing the dollar USDJPY, -0.08% and other rivals lower. 
 
 Read: China shares wipe out 2015 gains as stocks tumble 8.5% 
 
 In Europe, stocks followed Asia’s lead as the Stoxx Europe 600 dropped 5.3%, falling deeper into correction mode. 
 
 Gold prices US:GCZ5 failed to score any gains on Monday, despite its reputation as a refuge in times of market turmoil. The yellow metal fell 0.5% to settle at $1,153.60 an ounce. 
 
 Providing critical information for the U.S. trading day. Subscribe to MarketWatch's free Need to Know newsletter. Sign up here. ||||| An electronic board shows Hong Kong share index outside a bank In Hong Kong, Thursday, Oct. 11, 2018. Asian markets tumbled on Thursday, after Wall Street slumped on a heavy selling of technology and... (Associated Press) 
 
 An electronic board shows Hong Kong share index outside a bank In Hong Kong, Thursday, Oct. 11, 2018. Asian markets tumbled on Thursday, after Wall Street slumped on a heavy selling of technology and internet stocks. (AP Photo/Kin Cheung) (Associated Press) 
 
 SINGAPORE (AP) — A stock market rout that started on Wall Street rolled through Asia on Thursday, driving China's benchmark to a four-year low and sending indexes in Japan, Korea and Australia plunging. 
 
 Japan's benchmark fell by an unusually wide margin of 3.9 percent and China's main index lost 5.6 percent. Markets across Southeast Asia recorded similar declines. 
 
 Investors are wary of possible further U.S. interest rate hikes. That will raise the cost of corporate borrowing and could drag on economic growth. 
 
 The U.S. Federal Reserve recently raised short-term interest rates for the third time this year, with one more expected before the year ends. Strong economic data and a positive outlook from Fed officials have led to a sell-off in U.S. Treasury bonds, particularly longer-term ones, sparking concerns about even higher interest rates. 
 
 On Wednesday, President Donald Trump said the Fed "is making a mistake" with its campaign of rate increases. "I think the Fed has gone crazy," he charged. 
 
 Stephen Innes of OANDA said that Trump's comments have unsettled traders and put pressure on the dollar. "Equity markets were pulverized today as investors remain in full out retreat and even the most pessimistic of equity bears are still in shock by the sheer magnitude of the move," Innes said. 
 
 "This meltdown isn't just a mild case of the sniffles, suggesting the latest sneeze from the U.S. equity market could morph into a global markets pandemic," he added. 
 
 Sentiment also has been dampened by the spreading U.S.-Chinese tariff fight over Beijing's technology policy. U.S. officials have accused China of meddling in its midterm elections and stealing trade secrets from its companies through spies. 
 
 The International Monetary Fund cut its outlook for global growth this week, citing interest rates and trade tensions. 
 
 Tokyo's Nikkei 225 gave up 3.9 percent to 22,590.86 and the Shanghai Composite lost 5.6 percent to 2,573.11. Hong Kong's Hang Seng index shed 3.8 percent to 25,192.26. The Kospi in South Korea fell 4 percent to 2,139.51. Australia's S&P/ASX 200 slipped 2.7 percent to 5,883.80. Stocks plunged in Taiwan and fell across Southeast Asia. 
 
 U.S. stocks slumped on Wednesday as concerns over rising interest rates and trade tensions caused a sell-off in technology and internet stocks. The Dow Jones Industrial Average suffered its worst loss in eight months, falling 3.1 percent to 25,598.74. 
 
 The S&P 500 index sank 3.3 percent to 2,785.68. The Nasdaq composite, which has a large contingent of technology stocks, was 4.1 percent lower at 7,422.05. It has fallen 7.5 percent in just five days. The Russell 2000 index of smaller-company stocks shed 2.9 percent, to 1,575.41. 
 
 Apple and Amazon, the two most valuable companies in the S&P 500, each had their worst day in 2½ years. Apple slipped by 4.6 percent while Amazon lost 6.2 percent. 
 
 Amazon has soared 50 percent this year, but its stock has fallen 14 percent from its all-time high in early September. 
 
 Francis Tan, an investment strategist at UOB Private Bank, believes that the markets will pick up in the U.S. session. "The valuation of U.S. stocks, especially tech stocks, is still pretty high and there could be some profit taking actions now," Tan explained. 
 
 The dollar eased to 112.24 yen from 112.27 yen late Wednesday. The euro rose to $1.1547 from $1.1523. 
 
 Oil futures fell. U.S. crude gave up 96 cents to $72.21 a barrel. The contract settled at $73.17 in New York. Brent crude, the international standard, dropped $1.18 to $81.91 a barrel. 
 
 ___ 
 
 AP Business Writer Joe McDonald in Beijing contributed to this report.
– It might be the worst day yet in an already lousy year for the stock market: The Dow was down more than 500 points shortly after noon, a fall of about 3.3%, and the Nasdaq and S&P 500 were down similar percentages. The news comes after yet another bad day for Asian stocks, with Japan's Nikkei falling into bear territory—roughly defined as 20% below a recent high, reports the Wall Street Journal. One huge, familiar factor: Oil prices continue to fall, with the price of a barrel now under $27 a barrel. "Obviously we're in the throes of an environment where sentiment is not positive about risk assets, so it takes very little to put pressure ... pressure coming from falling oil prices continues to serve as a cues for equities to follow suit," a strategist at Janney Montgomery Scott tells CNBC. This MarketWatch piece suggests "the bear market in stocks has finally arrived" for US investors.