Dust storms are once again rolling across Arizona, leading to a series of crashes that killed one person and shut down Interstate 10 for hours. Another six people are in critical condition following the three accidents yesterday, the Arizona Republic reports. One pile-up involved 16 vehicles, the BBC notes. "The dust storms are the worst we've ever seen," says one official. Visibility was so poor at the time that the injured were driven, not flown, to the hospital. (More dust storm stories.)