SANTIAGO DE COMPOSTELA, Spain — The interior minister announced Saturday that the driver whose speeding train crashed, killing 78 people, is now being held on suspicion of negligent homicide.

Minister of Interior Jorge Fernandez Diaz announced the step against Francisco Jose Garzon Amo, who previously had been detained on suspicion of recklessness.

The minister also said Garzon Amo, 52, has been discharged from the hospital and taken to a police station.

The country’s railway agency has said it was the driver’s responsibility to brake before going into the high-risk curve where the train tumbled off the rails and smashed into a wall. But it’s still not clear whether the brakes failed or were never used.

A blood-soaked Garzon Amo was photographed Wednesday being escorted away from the wreckage, at first by civilians who had hurried to the scene of the accident and then by police, but it is not clear just what his medical status is.

In Wednesday’s crash, the train’s eight carriages packed with 218 passengers blazed far over the speed limit into a curve and violently tipped over. Diesel fuel powering the engine sent flames coursing through some cabins.

The president of Adif, the Spanish rail agency, said that the driver should have started slowing the train 4 kilometers (2.5 miles) before the dangerous bend. He said signs clearly marked this point when the driver must begin to slow.