March 23 (Bloomberg) -- BP Plc said part of its Texas City, Texas, crude-oil refinery, the third largest in the U.S., exploded and caught fire, causing ``multiple'' injuries and an unknown number of fatalities.

``BP can confirm fatalities as a result of the incident, but the number is not yet known,'' BP spokesman Hugh Depland said in an e-mailed statement. ``There have been multiple injuries, and one person has been life-flighted from the scene.''

The explosion drove gasoline futures on the New York Mercantile Exchange to an all-time high of $1.608 a gallon in after-hours electronic trading. Gasoline was up 1.85 cents to $1.5934 a gallon at 6:04 p.m. in New York.

The incident occurred around 1:20 p.m. local time in a unit that makes components used to raise the octane level of gasoline, BP spokesman Scott Dean said. The fire was extinguished about an hour later.

Other parts of the refinery continued operation, Dean said. The cause of the explosion and the extent of damage weren't known, although terrorism isn't suspected, refinery manager Don Parus said.

``It felt like an 18-wheeler, like a truck hit the building,'' Melissa Abbott, manager of a Kroger Co. store four blocks from the refinery, said in a telephone interview.

The injured were taken to the University of Texas Medical Branch in Galveston, spokesman John Koloen said.

Critical Injuries

``We know there's more than 10 casualties,'' Koloen said. ``Eight are in the trauma center. Three are in critical condition, one is in serious condition and the other four are being assessed.''

The sprawling refinery, which can process 470,000 barrels of oil a day, is London-based BP's largest. Built in 1934, the complex stretches over 1,200 acres and has about 1,512 workers.

Retail gasoline prices in the U.S. are already at a record high of $2.109 a gallon amid surging worldwide demand and crude- oil prices. Refiners boost production from March through June to supply filling stations as demand peaks during the summer travel season.

Gasoline inventories along the Gulf Coast, which produces 40 percent of U.S. supplies, dropped 4.2 percent last week to the lowest since Sept. 24, Energy Department figures showed.

BP's Texas City plant makes up about 2.8 percent of U.S. oil refining capacity, based on Energy Department data. BP operates five refineries in the U.S. with a total daily processing capacity of 1.5 million barrels.

`Monster Refinery'

``It's a monster of a refinery,'' said Ed Silliere, vice president of risk management at Energy Merchant LLC in New York. ``If gasoline production is affected at the refinery and it takes an extended time to fix, this is the wrong time for us to be seeing the loss of this unit.''

The incident also pushed oil futures higher. Crude oil for May delivery rose as much as 69 cents to $54.50 in electronic trading on the Nymex. The contract was up 26 cents to $54.07 a barrel at 6:12 p.m. in New York.

The explosion was at least the fourth incident in the past year at the Texas City refinery that caused injuries or a partial shutdown of the plant.

Three BP workers suffered serious burns in September in an accident at a water pump at the refinery. In August, a fire shut a diesel production unit. A March 2004 explosion and fire damaged a gasoline production unit.

BP is the fourth-largest refiner in the U.S. ConocoPhillips of Houston is the largest, followed by Exxon Mobil Corp. of Irving, Texas, and Valero Energy Corp. of San Antonio.

Exxon Mobil plants in Baytown, Texas, and Baton Rouge, Louisiana, are the nation's biggest refineries, according to U.S. Energy Department data.

To contact the reporter on this story: Bruce Blythe in Chicago at bblythe@bloomberg.net.

Last Updated: March 23, 2005 18:25 EST