New York, Dec 29 (IANS): US stocks dropped Wednesday with the S&P 500 back to negative territory for the year, as sentiment was still pressured by lingering European concerns.

Italy Wednesday successfully sold 9 billion euro 6-month bonds at 3.251 percent, just half of the 6.4 percent yield last month, suggesting that the country's borrowing cost significantly decreased, reports Xinhua.

However, the positive news failed to lift the market as uncertainties remained on peoples' mind.

The European Central Bank said that European banks deposited a record 452 billion euros overnight at the bank, reflecting that the banks were reluctant to purchase European sovereign debt as the central bank had hoped and also lacked mutual trust to lend to each other.

Meanwhile, euro slid to the lowest level since January, as investors were cautious waiting a more critical 10-year bond auction in Italy, which was scheduled Thursday, also spurring further sell-off in stock markets.

As of Wednesday's close, the Dow Jones industrial average lost 139.94 points, or 1.14 percent, to 12,151.41. The Standard & Poor' s 500 was down 15.79 points, or 1.25 percent, to 1,249.64. The Nasdaq Composite Index fell 35.22 points, or 1.34 percent, to 2, 589.98.