The driver of the train that crashed near the Spanish city of Santiago de Compostela, killing 79 people, has been provisionally charged with multiple cases of reckless homicide.
A court statement said Francisco Jose Garzon Amo had been released but has surrendered his passport to a judge.
Mr Garzon had arrived at court in handcuffs to appear before the investigating judge.
He is suspected of driving too fast on a bend.
The court statement said Mr Garzon must appear before a court once a week and is not allowed to leave Spain without permission.