A massive fire has erupted near the Ohio-Pennsylvania border after a train derailed in the area.
Authorities in Columbiana County are responding to the incident in East Palestine.
Local media reports said that emergency crews had been evacuating residents from their homes within a mile (1.6 km) of the fire.
East Palestine mayor Trent Conaway said at a news conference at midnight on Friday that an evacuation order was in place until further notice.
He urged residents in neighbouring areas to stay at home and stay off the roads while the fire is being tackled.
Authorities have not yet confirmed any injuries or casualties.
In a statement on Facebook, East Palestine Information said shelters are available from Taggart Road to Pleasant Street in the area for those being evacuated.
Norfolk Southern Railroad said: “We are aware of the derailment in East Palestine, and are coordinating closely with local first responders while mobilizing our own teams. We will share more details as they become available.”
Fire department teams from Ohio, Pennsylvania and West Virginia have also been roped in to assist operations.
It is not clear what the train was carrying at the time of derailment.
Images on social media show multiple train cars on fire in the small town northwest of Pittsburgh.
Smoke can be seen rising from the blaze and filling the air.
Videos on social media also showed police walking from door to door with loudspeakers ordering evacuations.
Additional reporting by agencies