A Washington state truck driver who apparently fell asleep at the wheel before swerving into oncoming traffic, killing a woman in a car and striking a school bus filled with children, was cited for causing a collision last year, officials said. Truck driver Kenneth Hahn, 54, of Yakima was cited just over a year ago for veering across the center of a roadway near the scene of the fatal crash, causing an injury collision, said Washington State Patrol Trooper Darren Wright. An initial accident report crash on state Route 97 north of Orondo, about 150 miles east of Seattle, said Hahn fell asleep while driving. Investigators were working to determine if drugs or alcohol played a role and if charges will be filed. "The charges if any for this collision will not be determined until we conduct a complete investigation," Wright said. One woman was killed and more than 50 people, most of them children headed to school, were sent to the hospital. Hahn's box truck crossed the center lane into oncoming traffic, crashing into a car driven by Carmela Cuellar Morales, 22, of Orondo, who died at the scene. A 12-year-old girl in her car was treated at the hospital and released, officials said. The driver of the school bus, Pamela Robertson, 53, swerved as the truck careened toward her, helping to prevent serious injury to the nearly 50 children on board, Wright said. "Her actions in my opinion reduced the impact and most likely contributed to the very limited number and severity of injuries to the students," he said. Robertson was hospitalized with non-life threatening injuries at Central Washington Hospital and was recovering, a hospital spokeswoman said. The children were taken for evaluation on Thursday and released to their parents, the hospital said. Hahn and a 36-year-old passenger in his truck also were treated for non-life threatening injuries, she said. (Reuters)