Is this the cause of the fatal Spanish train collision?

Investigators have identified a possible cause of a collision between two high speed trains in southern Spain.

On Sunday evening, an Iryo train collided with an Alvia express train operated by state rail company Renfe in Adamuz in Córdoba province, Andalucia, killing at least 45 people and injuring 292.

A probe launched into the rail accident – Spain’s worst since the Santiago de Compostela high speed derailment in 2013 – has focussed on a defect in the track as a possible culprit.

With human error on both drivers ruled out, investigators believe a fractured section of rail sparked a deadly sequence of events which caused both high speed trains to career into each other within 20 seconds.

Iryo train 6189 was travelling from Malaga to Madrid when it derailed at 7.43pm and was hit moments later by the Renfe train travelling in the opposite direction from Madrid to Huelva.

Preliminary findings show that markings were discovered on the wheels of the several carriages of the Iryo train, consistent with the 40cm break in a piece of track which experts believe likely fatigued over time.

By the time the sixth carriage passed the defective track head, it completely gave way, derailing the last cars and leaving them obstructing the adjacent line where they would collide with the other oncoming train.

With both trains travelling at more than 200 kilometres per hour there simply wasn’t time to stop either of the vehicles and prevent the tragedy from occurring.

At least three other trains that had travelled through the same section of line in the hours leading up to the crash were found on examination to have the similar dents on their wheels.

The rail samples are now being further tested at a specialist metallographic laboratory.

Several possible explanations exist for the faulty track, including a manufacturing defect or an impact from another train.

In a press conference on Friday, transport minister Oscar Puente said the latest findings were not ‘definitive’ but were an important update.

Opposition parties have blamed the disaster on a failure to adequately invest in infrastructure.

Spanish railway infrastructure manager Adif said that the section in Adamuz had been upgraded last May and had been inspected several times since, most recently on January 7.

A black box recording of the conversation between the Iryo driver and an operator in Madrid revealed the driver was unaware of the severity of the emergency after he had derailed.

On the tape, the control room operator also assures him that ‘no other trains were arriving’ in the area, also unaware that the Alvia train had already collided.

Another controller was speaking to a staff member onboard the Renfe service bound for Huelva, on which the train driver had already been killed.

In a chilling moment, she is heard repeatedly telling the control centre: ‘I have blood on my head.’

Among survivors was a six-year-old girl whose parents, brother and cousin had all died in the crash The family had travelled to the capital to watch a football match and the Lion King musical.

A missing dog which was travelling on the Iryo train was later found alive by firefighters on Thursday.

Spain’s high speed network is the world’s second largest with more than 3,000 km of track in operation, handling more than 25 million passengers annually.

The incident was one of at least four across the Spanish network this week, as Storm Harry battered much of Catalunya causing a commuter train to derail in Gelida, killing the driver, on the outskirts of Barcelona on Tuesday.

Heavy rain was thought to be behind the sudden collapse of a wall causing the Rodalies train

Local trains across the north east region of Spain were suspended for several days while the infrastructure was inspected following the torrential rain, with disruption continuing on most lines this weekend.

Another Catalan commuter train derailed between Blanes and Massanet-Massanes.

In a fourth incident, several people were injured after another train hit a construction crane in Cartagena, Murcia.

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