Frenzied oil trader at New York Mercantile Exchange yells during early trading, Tuesday, Aug. 30, 2005

World oil prices have surged to over $70 a barrel as investors worry about the impact of Hurricane Katrina on oil production in the United States.

Prices rose past $70.50 for a while Wednesday in Singapore, one day after a record of $70.85 a barrel was reached in New York trading before falling back.

The powerful hurricane tore through an area that produces about 25 percent of the U.S. crude oil output, shutting down key refineries and some oil drilling rigs in the Gulf of Mexico.

Even before the hurricane, world oil prices were at high levels as strong demand from China, India and the United States strained the ability of oil producers and refiners to get products to market.

Some information for this report provided by AFP and AP.