A U.S. town narrowly escaped tragedy when a train carrying crude oil derailed and exploded nearby, its mayor said Tuesday, calling for changes in how the fuel is transported across the country. No one was hurt in Monday's derailment that sent a huge fireball and black smoke into the sky just outside Casselton. The cause was under investigation, AP reported. Most of the about 2,400 residents obeyed a recommendation to evacuate their homes as strong winds blew potentially hazardous smoke toward the town overnight, Mayor Ed McConnell said Tuesday.