A large natural gas line in north Texas erupted Monday after utility workers accidentally hit the line, sending a massive fireball into the air and leaving one worker missing hours after the blast, officials said. Johnson County Emergency Coordinator Jack Snow said searchers were scouring the charred area around the damaged line looking for the missing person. Thirteen other workers who were also at the site were accounted for, and there were no known fatalities, he said. The missing worker had just gotten down from a machine drilling utility pole holes when the line suddenly exploded. Other workers lost sight...