In company news, Smithfield Foods surged more than 25 percent after China's Shuanghui International agreed to acquire the beef and pork producer for $4.7 billion in cash.
Apple edged higher after the iPhone maker's CEO said the company would release several more "game changers" but stopped short of clarifying if the company was developing a smart-watch.
Sallie Mae gained after the student loan provider said it would split into two publicly traded companies and named Chief Operating Officer John Remondi as its new chief executive.
Nasdaq agreed to pay a $10 million fine for alleged securities laws violations resulting from its "poor systems and decision-making" during the Facebook IPO last May, according to the SEC.
Wal-Mart dipped after the big-box retailer pleaded guilty to charges that it improperly discarded hazardous waste such as bleach and fertilizer years ago.
And among earnings, Chico's tumbled after the women's apparel retailer reported weaker-than-expected quarterly results, hurt by an unusually cooler spring and increased promotions.
Meanwhile, Michael Kors rallied after the accessories maker reported better-than-expected earnings.
On the economic front, mortgage rates jumped to their highest level in a year last week, drying up demand for home refinancings, amid worries the Federal Reserve may begin to slow its stimulus efforts, according to the Mortgage Bankers Association.
Treasury prices added to their gains after the government sold $35 billion in 5-year notes at a high yield of 1.045 percent. The bid-to-cover, an indicator of demand, was 2.79.
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Meanwhile, U.S. prosecutors filed an indictment against the operators of digital currency exchange Liberty Reserve, accusing the Costa Rica-based company of helping criminals around the world launder more than $6 billion in criminal proceeds.
The indictment came after the Treasury Department warned in March that digital currency exchanges need to follow traditional anti-money-laundering rules. And earlier this month, the Department of Homeland Security froze a subsidiary of Tokyo-based exchange Mt. Gox that handles most of the trading in the fledgling virtual currency Bitcoin.