Some families evacuated in northern Ohio after a derailment and chemical spill could be out of their homes until late Friday.
The warning was issued Thursday by the city of Willard, located about 65 miles southwest of Cleveland.
Residents in a limited area were allowed home Thursday morning, and the city expects most residents to be allowed back home later in the day.
An area of more than 425 homes was evacuated after a train derailment late Tuesday damaged a railcar that leaked flammable liquid.
No injuries were reported.
The CSX railroad offered evacuated residents a free Thanksgiving dinner to be served Thursday afternoon at Willard High School.