EAST PALESTINE, Ohio—A mechanical issue with a rail car axle caused the fiery derailment of dozens of freight cars in Ohio near the Pennsylvania state line Friday night, federal investigators announced Sunday. The smoldering tangle of cars, some carrying hazardous materials, kept an evacuation order in effect. Michael Graham, a board member of the National…

EAST PALESTINE, Ohio—Officials monitoring the smoldering, tangled wreckage of a train derailment in northeastern Ohio urgently warned hundreds of nearby residents who had declined to evacuate to do so Sunday night, saying a rail car was at risk of a potential explosion that could launch deadly shrapnel as far as a mile. They warned of…