WASHINGTON (AP) — At least 49 offshore oil platforms, all with production of less than 1,000 barrels a day, were destroyed by Hurricane Ike as it raced across the Gulf of Mexico, and some may not be rebuilt, the Interior Department said Thursday.

It said in the latest hurricane damage assessment that the platforms altogether accounted for 13,000 barrels of oil and 84 million cubic feet of natural gas a day. There are more than 3,800 production platforms in the Gulf producing 1.3 million barrels of oil and 7 billion cubic feet of gas each day.

Most remain shut down.

The report by Interior's Minerals Management Service said the agency was conducting helicopter flyovers of the Gulf waters to investigate unconfirmed reports of oil spills and oil sheens, but that it was too early to issue any definitive findings.

"There are no reports of oil impacting the shoreline or affecting birds and wildlife from releases in the Gulf of Mexico federal waters," said the agency.

The agency also said five gas transmission pipeline systems sustained damage, although the extent of damage is not yet known. It earlier had reported four oil drilling rigs had been destroyed and another damaged.

Meanwhile, the Energy Department reported that as of midafternoon Thursday, 12 of 31 refineries in Texas and Louisiana, with a total production capacity of 3 million barrels a day, remained shut down as a result of the hurricane that swept through the region on Sept. 13. A number of the others are operating at reduced runs.

More than 2.3 million electricity customers in six states as far away as Pennsylvania remain without power as a result of the hurricane and its aftermath of heavy rain, said the department. Of those, 1.6 million customers are in Texas.

Other states affected are Louisiana (18,804 customers), Kentucky (167,740), Indiana (36,800), Ohio (488,900) and Pennsylvania (16,730), according to the department.

About 93 percent of the Gulf's crude oil production remains shut down as does 77.6 percent of its natural gas production, said the Minerals Management Service.

The Energy Department said 10 of 39 natural gas processing facilities also were still closed as a result of the Hurricane Ike and Hurricane Gustav which hit two weeks earlier, giving the Gulf's energy infrastructure a glancing blow.

The Gulf region accounts for 25 percent of the country's domestic oil production, or about 1.3 million barrels a day, and 15 percent of its natural gas supplies, or about 7 billion cubic feet of gas a day.

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By H. JOSEF HEBERT

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