The driver of the train which crashed and killed 78 people in Santiago de Compostela on Wednesday is refusing to answer questions from police, according to Spanish newspaper El Pais.
Jaime Iglesias, police chief in the Galicia region, said that driver Francisco Jose Garzon Amo is being questioned "as a suspect for a crime linked to the cause of the accident".
Spanish media say the injured driver, who is under guard in hospital, is accused of "crimes related to the accident".
More top news
The Foreign Secretary described Jeremy Corbyn as a "mugwump" - but what does that obscure word mean?
Readers are shunning e-books in favour of their traditional counterparts, which sold last year at their highest level since 2012.
Glaucoma is the biggest cause of permanent blindness and affects 60 million people around the world - a tenth of whom are completely blind.