Chemical spill causes hour - long evacuation at Washington , D.C. 's Union Station . Cause of death was overheated battery system , official says . Regular subway service was to resume shortly after the evacuation lifted . First person taken to hospital for evaluation after complaining of pain . The train service was stopped for 75 minutes , official says .
Chemical spill causes hour - long evacuation at Washington , D.C. 's Union Station . Cause of death was overheated battery system , official says . First person taken to hospital for evaluation after complaining of pain . The train service was stopped for 75 minutes , official says .