(By Salman - iStockAnalyst Writer)Wall Street finished deep in red on Thursday as Jobless claims rose more than the forecast and worries regarding weakness in the global economy intensified.

The Dow Jones industrial average (DJI) dropped 344.65 points (2.99%), to 11,188.23, while the Standard & Poor's 500 Index (SPX) fell 38.15 points (2.99%), to 1,236.83. The Nasdaq Composite Index (XIC) declined 74.69 points (3.20%), to 2,259.04. Declining stocks outnumbered advancing ones by 5 to 1 on the NYSE and by 4 to 1 on the NASDAQ.  Thursday’s trade marks the fourth day of losses for both the NASDAQ and the S&P 500, and the S&P 500's longest losing streak since January. The S&P 500 has lost 3.6 percent this week.

Weekly jobless claims data released by the Labor Department showed that the number of Americans staying on jobless rolls rose to 3.435 million, the highest since November 2003, in the week ended Aug. 23. First time claims for unemployment benefits increased by 15,000 to 444,000 last week. ADP Employer Services showed private employers cut 33,000 jobs in August. Output by manufacturers fell 3.7 percent, its steepest fall since the final quarter of 2001.

However, there were encouraging signs from the services sector with the Institute for Supply Management's non-manufacturing index, which captures almost 90 percent of the economy, rising to 50.6 in August. Economists projected 49.5, which would have marked the third consecutive month of contraction.

Caterpillar Inc. (NYSE: CAT), Boeing Co. (NYSE: BA) and United Technologies Corp. (UTC) were the major drag on indices. Caterpillar declined, losing 5.6 percent to $63.94. Boeing retreated 4.6 percent to $63.03, and United Technologies lost 3.8 percent to $64.88. Boeing also fell after its largest union rejected a contract offer, giving the world's largest plane maker 48 hours to revise it and avert a strike that may further delay the 787 Dreamliner.

Energy shares like Exxon Mobil Corp. (NYSE: XOM) and Chevron Corp. (NYSE: CVX) too dropped as Oil extended its slide.

Shares of technology companies tumbled. Networking equipment maker Cisco Systems (NASDAQ: CSCO) was a top drag on the S&P 500 and NASDAQ.

BlackBerry devices maker Research In Motion (NASDAQ: RIMM) was the top Nasdaq drag, falling 6.4 percent to $107.49. Shares of iPhone maker Apple (NASDAQ: AAPL) dropped 3.4 percent to $161.22.   Ciena Corp. (NASDAQ: CIEN) plunged 24 percent after saying telephone and cable-television companies are slowing equipment purchases.

Banks and brokerages fell 4.7 percent after bond investor Bill Gross warned of a "financial tsunami" Legg Mason Inc. (NYSE: LM) led financial shares lower with a 9.2 percent decline to $43.03 as Credit Suisse Group AG advised selling the asset manager. Shares of investment bank Lehman Brothers (NYSE: LEH) fell 10.5 percent to $15.17.