The driver of a Spanish train that derailed, killing at least 80 people, was under police guard in hospital on Friday after the accident, which an official source said was caused by excessive speed. A judge in Santiago de Compostela, capital of the northern Spanish region of Galicia, was assigned to investigate the accident. The judge ordered police to question the train's driver, named as 52-year-old Francisco Jose Garzon. It was not clear what kind of injuries the driver had suffered. He was not arrested, but he was under a police guard at the hospital and was expected to be questioned on Friday. State train company, Renfe said the driver was a 30-year veteran of the firm with more than a decade of train driving experience. He had been driving trains on this line for about a year, the firm said. The regional government said 95 people were still in hospital, 32 of them, including four children, in a serious condition. Medical experts were still trying to identify 13 of the bodies early on Friday, leaving distraught families to wait for definitive news. Video footage from a security camera showed the train, with 247 people on board, hurtling into a concrete wall at the side of the track as carriages jack-knifed and the engine overturned. The train entered the bend at 190 km per hour (120 mph), according to local media reports. The speed limit on the curve was 80 km per hour (50 mph). Investigators are trying to find out why the train was going so fast and why security devices to keep speed within permitted limits had not slowed it down. The impact was so huge one carriage flew several meters into the air and landed on the other side of a concrete barrier. Bodies were strewn next to the tracks in the aftermath.