Stocks wiped out their earlier gains to close lower for a second session Wednesday, after the Fed's policy meeting announcement and as investors remained cautious following some weak corporate guidance.
Major U.S. Indexes
The CBOE Volatility Index, widely considered the best gauge of fear in the market, fell near 18. (Read More: Stocks Could Fall 20% From Recent Highs—Marc Faber)
Most key S&P sectors finished lower, led by energy and utilities.
The Fed's policymakers announced that rates will likely be kept exceptionally low through at least mid-2015, adding that the central bank will continue purchases of MBS at a pace of $40 billion per month. The Fed also said economic activity has continued to expand at a moderate pace in recent months.
Meanwhile, fellow Dow component AT&T fell after the mobile service provider posted revenue below expectations and added fewer new subscribers in the quarter than expected. Rival Verizon Wireless dged higher.
Facebook soared more than 20 percent after the social-networking giant reported its revenue surged 32 percent, topping expectations, thanks to gains in mobile. At least four brokerages boosted their price targets on the company, while Citigroup, BofA Merrill and Stifel raised their rating to "buy."
Among other social media companies, Yelp jumped after the firm pre-announced third-quarter revenue that was better than analysts had expected. In addition, the company said it acquired Qype, Europe's largest local reviews site, in a deal worth about $50 million.
Meanwhile, Netflix reported its revenue gained in the third quarter, but shares of the online movie-streaming website plummeted after its streaming forecast fell short of expectations. At least four brokerages cut their price targets on the firm.
Apple was higher a day after the tech giant unveiled a smaller version of the iPad and also took the wraps off several other devices, including updated versions of the MacBook Pro, the iMac and Mac Mini. (Read More: Best Days Over for Apple Stock?)
Monster Beverage jumped more than 10 percent to lead the S&P 500 gainers, recovering from a 23-percent plunge for the week, after the firm defended the safety of its energy drinks on the heels of a lawsuit and after the FDA said it is investigating reports of several people dying after consuming the company's energy drinks.
On the economic front, new home rose in September, according to the Commerce Department, hitting the highest since April 2010. Meanwhile, weekly mortgage applications tumbled last week as demand for both purchase loans and refinancings fell, according to the Mortgage Bankers Association.
The China HSBC Flash Manufacturing PMI showed that growth shrank for the 12th straight month in October, but output hit a three-month high and order books were at their strongest since April, signaling a strengthening recovery.
But businesses in the euro zone suffered their worst month in October since the last recession more than three years ago, according to the Markit's Composite PMI. Still, European shares ended higher.
Meanwhile, Greece was granted a two-year extension to meet the terms of its international bailout program, according to Greek finance minister Yannis Stournaras. Previously, Greece had until the end of 2014 to meet its target.
Treasury prices declined after the government auctioned $35 billion in 5-year notes at high yield of 0.774 percent and bid-to-cover of 2.73.
—By CNBC's JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC)
Coming Up This Week:
THURSDAY: Durable goods orders, jobless claims, Chicago Fed nat'l activity index, pending home sales, Kansas City Fed survey; Earnings from Altria, AstraZeneca, ConocoPhillips, P&G, Aetna, AutoNation, Credit Suisse, Dow Chemical, Pulte, Sprint, United Continental, Apple, Amazon.com, Coinstar
FRIDAY: GDP, consumer sentiment, Windows 8 released; Earnings from Comcast, Merck
More From CNBC.com: