A commuter train has derailed on arrival in Buenos Aires, injuring 31 passengers and causing traffic chaos in Argentina's capital. Most of the injuries involved people who were in the last car in the Mitre line formation, which swung off the rails and slammed into a metal signal tower in the Retiro station's rail yard on Monday. The tower then fell on top of the train, AP reported. Emergency medical director Alberto Crescenti said 25 were treated for shock at the scene and six others were hospitalized.
