A collision between a truck and a school bus Thursday afternoon on a California freeway killed ten people and injured dozens more.

News sources say the accident happened when the driver of a FedEx truck lost control of his vehicle and crossed a divider on Interstate 5 north of Sacramento. After striking a car, the truck hit a bus filled with Los Angeles-area high school students who were on their way to Humboldt State University in Aracata for a college tour. Witnesses said flames roared through both vehicles.

Three chaperones, the driver of the truck and bus and a number of students were among the dead. Thirty-four people were taken to area hospitals, some of them with severe burns.

The National Transportation Safety Board has launched a go-team to investigate a crash.