NEW YORK, Oct. 18 (Xinhua) -- Oil prices kept falling on Thursday, as a larger-than-expected increase in U.S. crude stockpiles continued to weigh on the market.

The U.S. Energy Information Administration (EIA) said in a weekly report on Wednesday that the country's crude stocks rose by 6.5 million barrels last week, well above market expectations and extending its rising streak to a fourth straight week.

A heavy sell-off in global equity markets also rattled nervous investors, with all the three major U.S. indices slumping over 1.7 percent in late trading on Thursday.

The West Texas Intermediate for November delivery dropped 1.10 U.S. dollars to settle at 68.65 dollars a barrel on the New York Mercantile Exchange, while Brent crude for December delivery lost 0.76 dollar to 79.29 dollars a barrel on the London ICE Futures Exchange.