In what could have resulted in a major collision, an electric train engine travelled for about 13 kms without a driver and was stopped only after railway staff chased it on a bike, boarded it and applied brakes. The incident took place on Wednesday in Maharashtra. The engine of the Chennai-Mumbai train was to be changed from electric to diesel at Wadi station. The electric engine was detached from the train so that a diesel engine could be joined as the route from Wadi to Solapur in Maharashtra is not electrified.