One student was killed and three others injured after their school bus crashed in North Texas. According to officials, the bus carrying 42 students from Terry Middle School crashed Wednesday afternoon. Aerial video showed the bus lying on its side in a ditch with its rear half showing scorch marks. Mesquite police say a power line struck by the bus ignited the fire, but the exact cause of the wreck remains under investigation. Three students, the bus driver and three officers were taken to hospitals with non-life-threatening injuries. The 38 other students were returned to the school where counselors met them and their families.