NEW BRIGHTON, Pa. -- After a massive train derailment left burning cars dangling over a river and forced hundreds of evacuations, local emergency officials said the possibility of another explosion still exists and decided to issue a state of emergency. As of noon on Sunday, two rail cars were still burning.

Crews have removed several of the cars from the wreck, but will continue working to remove the remaining cars form Beaver Creek and extinguish the final two cars.

A Norfolk Southern train jumped the tracks on a bridge in New Brighton at about 10:40 p.m. Friday, sending 23 cars over a bridge, according to the Beaver County Emergency Management Agency.

"The house kind of had a little shaking vibration, and I looked out the window and there's a fireball in the sky," said New Brighton borough manager Larry Morley, who lives several blocks away. "I started putting my shirt on and I knew I was going to work, but I didn't know what was going on."

Three of the tankers exploded, and eight rail cars on the bridge caught fire. None of them abutted homes or businesses, and authorities did not expect the fire to spread.

Flames continued to burn through Saturday night, and county emergency services director Wes Hill said there was concern that one more tanker could explode at any time.

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Detours: Route 18 is shut down. Truck traffic from the north: take Route 60 to Route 51; from the south, exit Route 18 in Rochester and take Route 51.

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Stay with WTAE Channel 4 Action News and ThePittsburghChannel.com all weekend for updates.

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Meanwhile, emergency officials downsized the immediate affected area -- their so-called "hot zone" -- to a grid bounded by Seventh Avenue and Second Street.

Hundreds of people who were evacuated were allowed to return to their homes for a short time to pick up clothing and medicines. They were told that they could be out of their homes for as long as three days.

Luckily, officials said, nobody was injured when the 80-car Norfolk Southern Railroad train, which was carrying ethanol, derailed above the Beaver River.

"There are cars on the bridge, hanging off the bridge and in the water," said Brian Hayden, spokesman for both the county Commissioner's Office and the county's Emergency Operations Center.

The ethanol is being left to burn itself out. Officials believed it was a non-toxic alcohol -- basically, grain alcohol -- that poses no toxic threat to the public. But toxicology tests were still given to the crew.

Firefighters were unable to extinguish the blaze until early Sunday, Hill said, so emergency workers used a compressor to blow air into the fire and help it burn.

Federal investigators with the National Transportation Safety Board have arrived, but vice chairman Robert Sumwalt said they would not enter the crash site until the fires were out.

The investigators have already relayed some preliminary evidence to Washington DC.

Robert Sumwalt, vice chairman of the safety board said that preliminary indications from the recorders showed that the train was traveling 36 to 39 mph when the cars derailed.

The train's midsection derailed while crossing the bridge, which is about 100 feet high and a half-mile long, Hayden said.

The site is about 25 miles northwest of Pittsburgh.

Witnesses reported hearing explosions and seeing flames shoot into the sky.

Sumwalt said the train was on its way from Chicago to New Jersey when it derailed.

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Related: More Beaver County News

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