NEW YORK (CNN/Money) - U.S. stocks tumbled early Thursday amid some weak economic data and Wal-Mart's sales miss ahead of chipmaker Intel's mid-quarter update.

Around 10:05 a.m. ET, the Dow Jones industrial average lost 184.21 to 8,240.91. The Nasdaq composite lost 34.37 to 1,257.94. The Standard & Poor's 500 index gave back 20.38 to 873.02.

Losses accelerated when the Institute for Supply Management's August report on the services sector. The index came in at 50.9, down from 53.1 in July and well below the 54 forecast of economists.

The government's July reading on factory orders came in as expected with a strong surge of 4.7 percent after a 2.4 percent drop in June.

Kicking off the August sales reports, discount chain powerhouse Wal-Mart Stores (WMT: down $1.93 to $50.41, Research, Estimates) reported a 3.8 percent increase for its same-store sales, or stores open at least a year -- falling short of company expectations and well below year-earlier levels.

Wall Street finally hears from tech bellwether Intel (INTC: down $0.84 to $15.27, Research, Estimates). The chipmaker delivers its much-anticipated mid-quarter update after the close of trading. Analysts this week cautioned that the company may narrow its sales and earnings estimates to the lower end of its range amid continuing weakness in information technology spending by corporations.

Investors shrugged off a pair of better-than-expected economic reports on labor and productivity -- two out of a quartet of the day's updates. Jobless claims fell to 403,000 in latest week, while second-quarter productivity growth was revised up to 1.5 percent from an expected 1.1 percent.

The Dow Jones industrial average pulled off a 117-point gain Wednesday, making back about a third of the loss posted in Tuesday's first-of-the-week trading session. The Nasdaq composite index was more than 28 points higher.

Asia-Pacific stocks finished mostly lower Thursday, although Tokyo's Nikkei index bounced off 19-year lows with a 1.6 percent advance. European markets began their sessions with declines.

Treasury prices rose in early trading, sending the 10-year note yield down to 3.91 percent from 3.95 percent late Wednesday. The dollar slipped against the euro, which neared parity with the U.S. currency, and was weaker versus the yen.

Brent oil futures rose 13 cents to $27.23 a barrel in London, where gold was solidly higher in early trading.