Futures extend losses after economic reports; CSCO tumbles

U.S. stock index futures added to their losses across the board Thursday following a mixed batch of economic reports and as investors continued to gauge when the Federal Reserve might start to reduce its $85 billion in monthly bond purchases.

On the economic front, weekly jobless claims fell 15,000 to a seasonally adjusted 320,000, hitting the lowest level in nearly six years, according to the Labor Department. Economists polled by Reuters had expected a reading of 335,000.

Meanwhile, New York state's manufacturing sector growth slowed to 8.24 in August from 9.46 in July, according to the latest report from the New York Federal Reserve. Economists had projected a reading of 10. A reading above zero indicates expansion in the sector.

And industrial production was unchanged in July as a decline in manufacturing output and utilities counteracted an uptick in mining activity, according to the Federal Reserve. Economists polled by Reuters had expected a gain of 0.3 percent.

Consumer prices edged up 0.2 percent in July, matching expectations, according to the Labor Department.

St. Louis Fed President James Bullard reiterated his comments from Wednesday that the central bank should wait for further evidence that the economy is firming before winding down its asset-purchase program.

"The committee still needs to see more data on macroeconomic performance from the second half of 2013 before making a judgement in this matter," Bullard said in remarks prepared for delivery to a breakfast event hosted by the St. Louis Fed.

(Read more: Worst case for Fed taper: mere market 'indigestion'?)

Among earnings, Wal-Mart Stores declined after the world's largest retailer reported disappointing quarterly and cut its revenue and profit forecasts for the year.

Kohl's climbed even after the department store chain forecast current-quarter earnings below expectations after reporting a decline in second-quarter profit.

Cisco Systems posted earnings and revenue that edged above Wall Street expectations but shares tumbled heavily after the network equipment maker said it would cut 4,000 jobs in the face of uncertain demand for its products.

Dell, Applied Materials and Nordstrom are among notable companies slated to post earnings after the closing bell.

Billionaire investor Warren Buffet's Berkshire Hathaway sharply reduced its holdings of Kraft Foods and Mondelez during the second quarter, according to Berkshire's quarterly filing with the SEC. Kraft Foods and Mondelez were created by a split up for Kraft Foods last October.

Meanwhile, Berkshire raised its stake in automaker General Motors to 40 million shares and reported a new stake in satellite television provider Dish Network of nearly 550,000 shares, worth approximately $24 million.

—By CNBC's JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC)

On Tap This Week:

THURSDAY: Treasury int'l capital, industrial production, housing market index, Philadelphia Fed survey, e-commerce retail sales, natural gas inventories, Fed balance sheet/money supply, Ford analysts mtg; Earnings from Dell, Applied Materials, Nordstrom
FRIDAY: Housing starts, productivity & costs, consumer sentiment

What's Trending on CNBC.com: