Crude prices tumbled along with equities on fears that energy demand would crumble if the world is engulfed by another recession.
New York's main contract, West Texas Intermediate light sweet crude for September delivery, dived USD 1.69 to USD 80.69 a barrel in early Asian trade, while Brent North Sea crude for October dipped 68 cents to USD 106.31.
Phillip Futures said in a market commentary that weak US economic data "provided a fresh blow to shaky investor confidence".
New claims for US unemployment insurance rose last week, ending a brief respite below the 400,000 threshold in the troubled jobs market, government data showed Thursday.
Initial jobless claims climbed more than expected to 408,000 in the week ending August 13, a gain of 9,000 from the prior week. The claims rise topped the average analyst estimate of 400,000, pointing to a weak labour market.
US inflation also roared back in July at the fastest pace since March, squeezing consumers just as the economy appears to be veering toward recession, according to government data.
Fears of another global meltdown were heightened after Morgan Stanley said in a report that the United States and Europe were dangerously close to recession, and that growth in the big emerging economies would be slower than it earlier forecast.