The driver of the train that derailed in Spain last week, killing 79 people, was talking on the phone to the train company at the time of the accident.
A court has analysed the train's data recording devices and says it was travelling at twice the 80 km/h speed limit for the curve where it went off the tracks near the city of Santiago de Compostela.
The initial reading of the black boxes show the driver, Francisco Garzon, received a call from the state train operator minutes before the accident to discuss the route to its destination.
The court says by the conversation and background noise picked up on the black boxes, Mr Garzon appeared to be consulting a map or some kind of paper document while on the phone, Reuters reports.
The train was travelling at 192 km/h in the minutes before it derailed in a curve where speed is limited at 80 km/h, according to the two black boxes located at the front and the back of the train.
The eight-carriage train slowed to 153 km/h at the time of the crash after a brake was activated seconds before.
Mr Garzon, 52, admitted in a closed-door hearing on to taking the curve too fast, blaming it a momentary lapse, according to media reports.
He has been charged with negligent homicide by Investigating Magistrate Luis Alaez, who is also probing whether the train, the tracks or the security system that slow down the trains may also have been at fault.
Sixty-six people remained in hospital from the crash on 25 July, with 15 in critical condition.