About 100 people remained out of their homes early Friday because of a fire in a derailed tank car that sent a giant plume of toxic gases over the western Kentucky area for a second time in less than 24 hours.

A phosphorus-laden tank car on a derailed CSX Railroad train reignited Thursday night after cleanup crews uprighted it. Residents in the sparsely populated area near the wreck were kept away from their homes a second night."We're letting it burn out before it is placed on a flat bed and hauled away,"said Don Armstrong, spokesman for the state Disaster and Emergency Services Division in Frankfort.

Jack Hamilton, spokesman for the Hopkinsville Christian County Emergency Operations Center, said about 50 families near the wreck remained out of their homes. Most of the evacuees took shelter with family and friends.

"There were no other evacuations and none necessary at this time," Hamilton said. "The fire is small and will slowly burn out. Once it does, we can get this place cleaned up."

He said the tank car was uprighted at 7:30 p.m. when it reignited and sent a plume 400 feet high and 100 yards wide. He said no one was hurt.

Authorities said the first fire forced about 15,000 people from their homes in an eight-county area Wednesday night when the phosphorus car - one of 36 cars of the 80-car train - derailed and burned.

The train traveling from Nashville, Tenn., to Evansville, Ind., derailed about 3 1/2 miles north of Crofton, igniting a tank car - the only one carrying phosphorus, a chemical used in military explosives and soft drinks.

Thursday night's fire created a much smaller gas cloud that moved north and northeast. About three dozen people suffered minor eye irritations, breathing difficulties, and other ailments related to Wednesday's original cloud "but nothing serious," said Mike Lynch, another DES spokesman.

As the fire burned Thursday afternoon in a 50-foot ravine, sand from about a dozen trucks was spread on and around the tanker by a bulldozer. About sundown, after other wrecked rail cars around the tanker were removed, crews tried to lift the tanker out of the ravine.

The cause of the derailment was believed to be expansion of the tracks from Wednesday afternoon's extreme heat, which prompted the railroad to issue a "slow order" that the train crew apparently was unaware of.

"It appears the engineer was going 35 mph under a 10-mph slow order," CSX spokesman Lloyd Lewis said.