Information from the two data-recording black boxes of the ill-fated train that derailed in Spain last week said that the driver, Francisco Jose Garzon Amo, was on the work phone and consulting a map when the accident occurred.

In a statement issued by the Superior Court of Justice of Galicia, which is leading the probe, it also said the train was travelling at 192 kilometres an hour prior to the crash, twice the speed limit of 80 kph.

"Seconds before the accident the brakes were activated. It is estimated that at the time of the derailment the train was travelling at 153kph," the court said in a statement.

Mr Amo was talking on the work phone to staff of Renfe, the operator of the state railway, because minutes before the derailment, the driver got a call on his work phone about the route he had to take to get to Ferrol.

The background noise and content of conversation indicated the driver was also consulting a map or a paper document.

The train, which had eight carriages, flew off the track while negotiating a bend and ploughed into a concrete wall, causing the death of 79 people and injured 66 more.

The investigation is also checking if the train, tracks or safety system designed to slow down trains could be faulty after finding out that the section of the track where the accident occurred does not have an automatic protection system on most of its high-speed lines.