Stocks saw an accelerated selloff in the final hour of trading, led by techs, and were on track to close lower for the fifth-consecutive week after a dismal monthly jobs report indicated signs of an economic slowdown.
The Dow Jones Industrial Average was down more than 90 points, sliding closer to its 144-point drop at the open, following a choppy sessionon Thursday.
AmEx and DuPont were among the blue-chip laggards. And tech bellwether Cisco tumbled to multi-year lows.
The S&P 500 and the tech-heavy Nasdaq also slumped. The CBOE Volatility Index, widely considered the best gauge of fear in the market, slipped below 18.
This is the first time the Dow has fallen five weeks in a row since July 2004, and the first time for the five-week stream by the S&P 500 since July 2008.
All key S&P 500 sectors fell, except for energy. All sectors were lower this week, which hasn't happened since the 2010 market lows in July.
The fact the S&P 500 has moved back above 1,300 after it broke through that level earlier in the day may be a good sign that the market isn’t ready to move much lower, said Marc Pado, market strategist at Cantor Fitzgerald.
But the fact stocks remain lower reflects caution on the part of traders. “You’re going to have a lot of negative headlines over the weekend plastered everywhere,” Pado said. “I’d rather go out the weekend a little bit cautious, and not be too long or too aggressive.”
Stocks took a hit at the open after nonfarm payrolls rose by only 54,000 in May, the smallest increase for jobs since September 2010, according to the Labor Department. Analysts surveyed by Reuters had expected to see 150,000 jobs added in May after a gain of 244,000 jobs in April, an 11-month high.
Private payrolls gained 83,000, while government payrolls fell 29,000, the government said. The unemployment rate rose to 9.1 percent, instead of falling to 8.9 percent, as expected.
"It's hard to look at the report and see any strength here," John Canally, economist at LPL Financial said of the jobs news, adding that the weakness isn't surprising at this point in an economic recovery. (Read More: Soft Patch? Economy Looks More Like It's In For Worse)
"You tend to get some data that’s choppy two years into a recovery," he said. "This is one of these times when the data is not all good."
Canally doesn't think the job news warrants a third round of bond buying or quantitative easing. But talk of what the market calls "QE3" emerged immediately after the numbers were released.
"Arguing about the merits of whether QE3 would be a good idea, is irresponsible right now," said Todd Schoenberger, managing director at LandColt Trading. "It would be proactive for the FOMC to discuss, and develop a strategy for implementing QE3; because it's painfully clear the United States is headed for a very messy second half of 2011."
There's a feeling, Schoenberger added, that the selling pressure will continue.
"It makes you very nervous as an equities trader going into this summer. There's not even a feeling of caution anymore, it's an uneasy nervousness that a lot of us will be carrying for a little while now," he said.
Stocks pared some losses following the ISM's report that the pace of growth in the services sector picked up modestly in Maywhile gauges of new orders and employment climbed.
Tech stocks were in the red with semiconductors such as Marvell Tech , Nvidia and Broadcom sliding broadly.
Research In Motion sagged after at least two brokerages cut price targets on the BlackBerry maker amid concerns over the firm's inability to tackle competition from rivals Apple and Google .
But the energy sector gained, led by oil services companies after the CEO of Baker Hughes said he expects the second half the year to be better.
Halliburton also climbed after RBC raised its price target on the oil driller to $65 from $60.
Chevron ticked higher even after news of an explosion at the firm's oil refineryin southwest Wales. The oil giant also said the sale of the facility to Valero Energy remains on track, and its output was not affected, according to reports.
Wal-Mart gained slightly after the big-box retailer's board approved a new share buyback program worth $15 billion to replace its existing program.
Shares of Quiksilver jumped more than 10 percent after the apparel retailer posted results that beat estimates, helped by robust domestic sales. In addition, Piper Jaffray raised the firm to "overweight" from "neutral."
Newell Rubbermaid saw the biggest percentage drop on the S&P 500, tumbling more than 10 percent, after the storage container maker cut its forecasts for the year and said current quarter results will miss expectations.
Orexigen Therapeutics plunged more than 30 percent after news the FDA would not approve the drug Contrave, an obesity drug.
GT Solar International jumped after news the solar and LED equipment maker received a $460.4 million order from a Chinese firm.
And Tesla gained after news that electric car maker was able to price a share offering at a higher price than expected. Funds from the offering will be used to develop Tesla's Model X SUV.
The dollar declined against a basket of currencies after the jobs report and as the euro surged after the European Union, International Monetary Fund and European Central Bank completed an inspection of Greece, and will make a tranche of international aid available for the troubled nation by early July.
Oil prices were mostly flat as U.S. light, sweet crude slipped 18 cents, to settle at $100.22 a barrel, while LondonBrent crude traded around $116 a barrel.
In Europe, stocks ended lowerand posted their sharpest weekly loss in 2-1/2 months, while traders in Asiabraced for policy tightening for China over the weekend.
On Tap Next Week:
MONDAY: Federal Reserve Chairman Bernanke speaks, Fed's Plosser speaks, Fed's Fisher speaks, Treasury STRIPS, Apple's annual developers conference.
TUESDAY: 3-year Treasury note auction, consumer credit; Fed's Dudley speaks, Fed's Lockhart speaks; Amazon shareholder meeting, Ford investor day.
WEDNESDAY: Weekly mortgage applications, McDonald's sales data, quarterly services survey, oil inventories, 10-year Treasury note auction, Fed's Beige Book; Fed's Hoenig speaks; Caterpillar shareholder meeting.
THURSDAY: Bank of England announcement, European Central Bank announcement; international trade, jobless claims, wholesale trade, 30-year Treasury bond auction, money supply; Lubrizol shareholders vote on Berkshire takeover; Fed's Plosser speaks, Fed's Yellen speaks; earnings from National Semiconductor.
FRIDAY: Import & export prices, Treasury budget; earnings from Lululemon Athletica.
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