MADRID — Spain's Transport Minister Oscar Puente has rejected calls for his resignation over the second train accident on his watch to cause mass casualties this year, as authorities worked on Friday to identify the victims of Wednesday's crash near the town of Urda in central Spain, which left at least 69 people dead, AAP reported, citing AP reporting.

Source: AAP / AP

"My duty now is not to focus on discussing whether I will remain in office but on solving the problem, determining exactly what happened and providing clear explanations," Puente said at a press conference on Friday. MPs from across the political spectrum this week condemned him for attributing the crash to a break in protocol by control-centre operators rather than accepting responsibility, and rail workers' unions have called for his immediate dismissal. Demonstrators also gathered outside the transport ministry in Madrid on Wednesday night.

The train that smashed into a second, stationary train was travelling at between 160 and 200 km/h when the collision occurred, according to a preliminary report released on Thursday by the Independent Authority for the Technical Investigation of Accidents and Incidents (AITAT). "The sequence of malfunctions, instructions and actions eventually led to the collision, in the absence of the necessary mitigating barriers," AITAT said, adding it could not confirm the exact speed until data is extracted from the train's black box.

The collision happened after several trains were automatically stopped following a failure of the signalling system, after which the central control centre in Madrid took over. A train operated by state-owned Renfe was authorised to proceed even though a stationary train operated by Iryo was ahead of it, according to Puente. The crash, on the Madrid-Seville high-speed line, followed another accident involving the same rail companies on the same line that left 46 people dead in January.

At the crash scene, large cranes were lifting the mangled wreckage as the Civil Guard listed 64 people as missing in what is already Spain's deadliest train accident since 2013. Authorities had carried out 49 autopsies and formally identified five people — three women and two men — Esther Padilla, a spokeswoman for the Castilla-La Mancha regional government, told the TVE network on Friday. Regional leader Emiliano Garcia-Page said no additional bodies were found when rescue teams overturned a carriage on Thursday, but added: "We cannot rule out the possibility that there may be more fatalities."

Prime Minister Pedro Sanchez on Friday vowed to find out what caused the accident. "It is unacceptable for a country like Spain, with such a strong high-speed rail system, to suffer two accidents of this nature and magnitude in a single year," he said. The crash has reopened debate about safety and maintenance on Spain's high-speed rail network, the most extensive in Europe, as the country prepares for a general election Sanchez has called for November 29.