Houston: A huge relief effort was accelerating in storm-struck Texas on Monday as the big oil centre of Houston struggled to get back to business after it was battered by Hurricane Ike.

About 2,000 people had been rescued from flooded areas in the largest such effort in the state's history as searchers scoured hard-hit places like the devastated island city of Galveston, which was shredded when the hurricane made landfall on Saturday morning before heading inland to Houston.

Twelve of the fifteen Texas oil refineries that had been shut as a precaution showed no visible signs of flooding or damage - a sign fuel production could resume more quickly than initially thought. But power outages could still hinder their start-up.

Oil prices fell below $100 [about Dh367] a barrel to a six-month low Monday on early signs that Ike may have spared important Gulf Coast infrastructure.

Over 4 million people, several refineries and many businesses and gas stations remained without power, but floods were receding as crucial aid such as ice, water and food was being delivered to distribution points.

"Sixty trucks with supplies rolled in earlier tonight. ... As we are standing here, deliveries are being made," Ed Emmett, chief executive for Harris County, which includes Houston, told a news briefing on Sunday night.

He added that six relief distribution points were already up and running and he expected 17 to be in operation by later yesterday.

The relief roll-out appeared to defuse tensions that flared between the Federal Emergency Management Agency and local officials as hard-pressed residents complained about the time it was taking to get supplies to those in need.

Local officials later attributed the rift to confusion over who was responsible for doing what in the relief chain, a situation that led to delays. The Bush administration came under heavy fire for its botched relief efforts in New Orleans after Hurricane Katrina in 2005.

Floods have been among the obstacles to rescue efforts and aid operations, but officials said the waters were receding.

Houston Mayor Bill White said all city employees were expected to show up to work on Monday as the country's fourth most populous city tries to get up and running again.

The city's two main airports were to resume partial operations on Monday, but with debris still littering its streets and windows blown out of office buildings, as well as power problems, it seemed unlikely the city of more than two million people would return to business as usual soon.