A bus crashed into a runaway circus elephant on Tuesday, killing one person and injuring 10, dpa quoted police as saying. The four-ton female elephant also died, and was left lying on the road that links Mexico City to the pyramids of Teotihuacan. "I untied her so she could eat. She had never done this before, but she suddenly rushed to break the gate. I could not stop her," the animal's caretaker, Marcelino Ramos, 22, told Mexican media. The elephant wandered about three kilometers away from the area where circus animals were kept, to a motorway, where she was hit by a bus ferrying about 40 people shortly after midnight. The bus driver died and six of the injured were taken to hospital, police said.