(AP) ROCKFORD, Ill.

One person was killed and a few others were severely injured when a Canadian National freight train derailed Friday night, triggering an explosion and fire involving 12 ethanol-filled tanker cars that continued to burn early Saturday.

Officials evacuated the area on the edge of Rockford, about 80 miles northwest of Chicago, amid concerns about air pollution and the chance that more of the train's cars might catch fire.

Winnebago County Coroner Sue Fiduccia said early Saturday the death was that of a female who had been in a car that was waiting for the train to pass a crossing near the derailment site. Fiduccia would not release the victim's name or age.

Rockford Fire Chief Derek Bergsten said three other people from the car ran from the vehicle when it was bombarded with flying railroad ties and were severely burned by flaming ethanol from the explosion.

The three were taken to OSF Saint Anthony Medical Center in serious to critical condition, and one of them was later airlifted to Stroger Hospital in Chicago, Bergsten said.

The fire chief said the eastbound train had 114 cars, 74 of which were tankers filled with ethanol.

Witnesses told the Rockford Register-Star that cars on the Chicago-bound train began hydroplaning in standing water just as it approached the crossing. Some of them left the tracks moments before two of them exploded.

Patrick Waldron, spokesman for Canadian National, said the two crewmen on the train escaped injury. The engine was able to pull 64 cars still attached away from the scene.

Authorities said they planned to let the fire burn itself out.

"The situation is not under control, but we are making progress in getting it under control," said Kirk Wilson, a fire chief in nearby Rockton. "It's very dangerous. It's very explosive. We're not risking any firefighters' lives."

Wilson, whose department was one of at least 26 that responded to the derailment, said he expected the ethanol to continue burning until later Saturday.

"We're letting the product burn itself out," he said. "We can't get too close to it. We're observing everything through binoculars from about 200 or 300 feet away."

The cause of the derailment was under investigation, Wilson said.

Officials evacuated residents from about 600 homes within a half-mile radius of the derailment, Bergsten said. The evacuees were being housed at a number of churches and private homes. Bergsten said potentially toxic fumes from the fire should keep them out of their homes until environmental officials give them the green light to return.

"At first I thought it was a tornado because they always say a tornado sounds like a train coming," said Jeff Tilley, a Register-Star employee who lives near the scene of the derailment.

Alicia Zatkowski, a spokeswoman for ComEd, said the derailment knocked out power to about 1,000 of the Chicago-based utility's Rockford-area customers.

The derailment is being investigated by Canadian National and the Federal Railroad Administration. Members of the National Transportation Safety Board were en route early Saturday.

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