EAST COUNTY — Eleven children riding on a school bus were injured Tuesday morning when the bus crashed into a light pole at the Golden Acorn Casino on the Campo reservation, authorities said. Ten of the children were taken to hospitals with complaints of minor injuries and one reportedly had moderate injuries. The students, who are fifth graders from Sunrise Elementary School in Yuma, Ariz., were transported by ambulance to Grossmont and Alvarado hospitals. The students were on their way to a field trip at Balboa Park. “They stopped here to walk and stretch their legs,” said casino spokesman David Baggerly. The accident was reported at 8:12 a.m. in the main parking lot of the casino, the California Highway Patrol said. Authorities had previously said that the bus collided with a private vehicle.