One school bus driver was killed and another was injured Tuesday afternoon when wind swept up a dust cloud that obscured a driver`s vision. The driver braked suddenly, causing a seven-vehicle pileup involving three buses that were on their way to Trumann`s Central Elementary School. The school superintendent says no students were on the buses at the time. Officials said the accident occurred on Arkansas 69 west of Trumann when the lead school bus driver, Jan Ham, lost sight of the road because of the dust cloud and stopped the bus. Ham, who also is the girl`s basketball coach, was injured and taken to a hospital. The name of the deceased driver was not immediately released.