Spain's transport minister, Óscar Puente, says he will not resign over the high-speed rail collision that has left at least 69 people dead. Speaking at a news conference in Madrid, he said he had "nothing to hide" and that "my duty right now is not to talk about whether I should remain in my position, but to resolve the problem."

Political rivals, a trade union and demonstrators have called for him to step down. The conservative People's Party joined calls for his resignation after the union CSIF made the same demand earlier this week. Puente said he would not budge, adding, "The easy thing for me would be to leave, but neither that fits with my character nor is it what the Prime Minister has asked me to do."

The crash happened on Wednesday near Urda, in Toledo province. A state-operated Renfe high-speed train hit the back of a stationary train operated by Iryo. A preliminary report from transport investigators, released late on Thursday, found the Renfe train was travelling between 160km/h and 200km/h when the collision occurred.

Puente said a computer failure at about 08:30 led to the initial halt of six moving trains, including the two that later collided. Leaked audio recordings published in Spanish media appear to show that one high-speed train was cleared to move even though another train had stalled about 25km ahead. Puente called that decision "inexplicable." He said on Friday he was "not going to use any worker as a shield" and that if the investigation finds human error, "we will act in consequence of that."

Prime Minister Pedro Sánchez said public trust in the high-speed rail network had been broken and called it "unacceptable" that two similar tragedies had occurred within a year. In January, a collision on the same Madrid-Seville route killed 46 people in Adamuz.

Spain is observing three days of mourning. Families of victims say they are still waiting for information from authorities. Esther San Emeterio, whose brother Pepe, 54, is still missing, said officials were leaving families in "uncertainty."