Officials were investigating a blast that leveled an explosives plant in rural Tennessee, as families of the 18 people missing and feared dead waited anxiously Saturday for answers. The explosion Friday morning at Accurate Energetic Systems, which supplies and researches explosives for the military, scattered debris over at least a half-mile (800-meter) area and was felt by residents more than 15 miles (24 kilometers) away, said Humphreys County Sheriff Chris Davis. MORE: https://www.wthr.com/article/syndication/associatedpress/officials-investigate-blast-at-tennessee-explosives-plant-that-left-18-missing-and-feared-dead/616-b8f21b6f-c454-4bc8-a4d1-af29654092aa