What is said to be the cause of the train crash?

Experts investigating the Spanish train crash which killed 79 people last week have told a court that data recorders fitted to the high-speed train show that it was traveling at 153 km/h, almost twice the speed limit for that section of track when the train derailed.But the court also says the driver Francisco Jose Garzon was talking on the phone to an official of the state railway company Renfe when his train jumped the rails and he was apparently consulting a piece of paper at the time.The court inquiry is still in its early stages but these suggestions will add to a sense of outrage which is mingled with grief across Spain.