Crews worked overnight to clear up hydrochloric acid that leaked from a tank car after a train derailed in mid-Michigan, and 35 people who were evacuated from nearby homes should be allowed to return later Friday, officials said.

Twelve railcars came off the tracks including four cars that were toppled in the 7 p.m. Thursday accident in Shiawassee County’s Vernon Township, said Canadian National Railway spokesman Patrick Waldron. No injuries were reported.

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Waldron said he didn’t know how much hydrochloric acid the train pulling about 100 cars had been carrying or was spilled. He said 10 railcars involved in the accident were carrying the corrosive solution, including one that had a “drip leak that was contained quickly.”

A freight-carrying box car and another car carrying ethanol also were involved. The train was heading from Battle Creek to a Canadian National yard in Flat Rock.

The leak is stopped and the vapors are stopped,” Vernon Township Fire Chief Dan Bannister told The Associated Press Friday morning, adding that repair and cleanup of the damaged and contaminated rails was the next priority. He said the nearest home was two-thirds of a mile away.

“Hydrochloric acid gives off corrosive fumes that can cause problems if you inhale them,” Bannister said. “It could cause irritation in the lungs … and it could also cause skin burns.”

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Waldron said four cars remained tipped over early Friday morning and eight derailed cars had already been removed from the site, near Durand, about 20 miles west-southwest of Flint. He said crews patched the railcar that spilled acid and were preparing to empty the remaining liquid into a tanker that would be trucked away.

The accident delayed an eastbound Amtrak passenger train that operates on the same track and diverted it to Lansing, Waldron said. He said a damaged rail line prevented other trains from passing through Friday morning. He was unable to provide details of service disruption.

Bannister said 12 evacuated families were briefly sheltered at Durand City Hall but Canadian National later made arrangements for them to spend the night at a local hotel. He said residents are expected to return home between noon and 2 p.m.

Canadian National environmental teams were working with local authorities on air monitoring and water testing as a precaution ahead of evacuations being lifted, Waldron said. He said it was not immediately known how many people were aboard the train at the time of the accident but that a  “typical crew is two.”

Waldron declined comment about the status of crew members, saying the company does not discuss the status of employees.

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No cause of the derailment has been determined. Canadian National and federal railroad administration authorities are investigating. 
(Copyright 2011 by The Associated Press.  All Rights Reserved.)