Crude prices tumbled Thursday as more weak U.S. economic data worsened concerns over U.S. recovery.

The bulk of U.S. economy slowed sharply in April on series of soft data released recently. On Thursday, the Institute for Supply Management's non-manufacturing composite index slowed to 53.5 from a very strong 56.0 in March, worse than expected. The retails sales also slowed in April, worsening concerns over U.S. economic recovery.

The Labor Department said the initial jobless claims dropped 27, 000 to a seasonally adjusted 365,000 last week, far more than economists had expected. But the upbeat report failed to boost market sentiment as Wednesday's ADP data showed that the private sector added only 119,000 jobs in April, about half of March's figure. Investors were also cautious awaiting for April's payroll report scheduled for Friday.

In Europe, worries over debt problems lingered. The borrowing costs for Spain jumped although its bond auction met strong demand.

On the supplies side, the Organization of Petroleum Exporting Countries (OPEC) said it was working hard to bring down oil prices by producing more. OPEC secretary general said on Thursday that the oil cartel was pumping much more than its official target.

Light, sweet crude for June delivery fell 2.68 dollars, or 2.55 percent, to settle at 102.54 dollars a barrel on the New York Mercantile Exchange. In London, Brent crude for June delivery slipped 2.12 dollars, or 1.79 percent, to close at 116.08 dollars a barrel, its lowest settlement since Feb.6.