A train derailment caused a huge fire to erupt in eastern Ohio on Friday night, prompting officials to order many of the town’s residents to evacuate as crews assessed whether the cargo contained toxic material, the authorities said.
The risk of injury remained a concern on Sunday because of the lingering threat of a potential explosion, officials said.
Roughly 50 cars derailed around 9 p.m. Friday in East Palestine, Ohio, which has 4,700 residents and is about 50 miles northwest of Pittsburgh.
On Saturday, local and federal officials and Norfolk Southern, the rail operator, were still investigating the cause of the derailment, which led to a fire that swept much of the town in smoke and cast a red glow over homes in the area overnight.
Gov. Mike DeWine of Ohio issued an urgent evacuation notice on Sunday night to more than 500 people who had previously declined to leave their homes and were within a one-mile radius of the derailment site.
“Within the last two hours, a drastic temperature change has taken place in a rail car, and there is now the potential of a catastrophic tanker failure which could cause an explosion with the potential of deadly shrapnel traveling up to a mile,” Governor DeWine said in a statement.
“Those with children in their homes who decline to evacuate may be subject to arrest,” Governor DeWine added.
There were no reports of injuries or deaths, Trent Conaway, the mayor of East Palestine, said at a news conference on Saturday. But 1,500 to 2,000 residents had been asked to evacuate the area near the derailment, officials said.
Videos and photos of the fire showed smoke swelling up in the night as emergency vehicles rushed to the site. On Saturday morning, some train cars continued to burn, putting out gray puffs across East Palestine. Officials said there had been several explosions, including some on Saturday morning.
It was not immediately clear how many train cars caught fire.
Keith A. Drabick, chief of the East Palestine Fire Department, said on Saturday that officials had monitored the air quality and “so far, everything is good.”
But, he added, the authorities were still unsure whether the material burning was hazardous. He noted that the train, which had been traveling from Madison, Ill., to Conway, Pa., was carrying some material that could be hazardous.
“If you have to come to East Palestine — don’t,” Chief Drabick said. “Stay out of the area until we can get this mitigated.”
The possible product that investigators were most worried about burning, he said, was vinyl chloride, a colorless and flammable gas that is toxic to people.
“The rail car that was carrying that is doing its job,” Chief Drabick said. “The safety feature of that rail car is still functioning.”
Drones were deployed to the site on Saturday to determine what was burning, he said.
The National Transportation Safety Board was investigating the incident. Ohio’s highway patrol and the emergency management and environmental protection agencies were responding as well. The governor deployed the Ohio National Guard to the derailment site on Sunday.
The sprawling fire led more than two dozen agencies from other states to go to East Palestine to help with containment and the investigation. Firefighters from Ohio, Pennsylvania and West Virginia also responded.
Officials said the main concern on Saturday was the potential for poor air quality. Mr. Conaway, who declared a state of emergency in the community, said he lived on the edge of the town and it smelled “horrible” there.
“Check on your family members if they have breathing problems,” he said. “You might want to get them out of here.”
April Rubin contributed reporting.
