A jetliner trying to land in heavy snow slid off a runway, crashed through a boundary fence and slid into a busy street, hitting one vehicle and pinning another beneath it Thursday. A child in one of the vehicles was killed. Two passengers on the Boeing 737 suffered minor injuries, and eight people in the two vehicles struck outside Midway International Airport were hurt in the incident, authorities said. The child, a 6-year-old boy, was dead on arrival at the hospital, spokeswoman Deborah Song said. Two adults and two other children were at the hospital, their conditions ranging from serious to good, she said. Ninety-eight passengers and five crew members were on board Southwest Airlines Flight 1248.