Preliminary report reveals likely cause of deadly Spanish train crash

Investigators have combed the area around the crash site for several days

A rail fracture likely preceded a high-speed train derailment in southern Spain last Sunday, killing 45 people, a preliminary report from the rail accident investigating body CIAF revealed Friday.

The collision in Adamuz, Cordoba province, saw a train from private consortium Iryo derail and collide with an oncoming high-speed service from state-owned Renfe.

The CIAF report stated: "Based on the information available at this time, it can be hypothesised that the rail fracture occurred prior to the passage of the Iryo train involved in the accident and, therefore, prior to the derailment."

Investigators added that the causes for the breakage remain undetermined, with nothing ruled out.

Reuters previously reported a broken joint on the track. The Transport Ministry and Iryo's majority owner, Italian state-controlled Ferrovie dello Stato, offered no immediate comment.

Investigators found uniform notches on several of the wheel treads on the right-hand side of the Iryo train, according to the report.

The crash, one of Europe's biggest, happened on Sunday night near the southern town of Adamuz in a remote hilly area, killing at least 45 people (Reuters)

The marks were consistent with the wheels striking the top of a rail, and a visual comparison suggested the wheel notches match damage seen on the broken rail section at the derailment site, it added.

CIAF said it had also found similar wheel damage on other trains that passed through the area before the crash.

The report's findings must be confirmed by further calculations and detailed analysis, CIAF cautioned.

The report comes after a large piece of metal discovered near the site was theorised to be the crucial missing undercarriage component investigators have been searching for to determine the accident's cause.

Inaki Barron, head of Spain's railway accident investigating body CIAF, said on Monday that the investigation would focus on a missing part, known as a bogie.

He highlighted its importance as the key point of contact between the speeding train and the tracks, suggesting it could shed light on the cause of the derailment.

Investigators have combed the area around the crash site for several days, cordoning it off, marking and photographing every piece of evidence on the track (Associated Press)

Reuters photographs from Tuesday showed the piece lying partly submerged in a small stream to the side of a railway bridge some 15 metres (49 ft) below the train tracks and some 300m from the crash site.

A spokesperson for the Civil Guard police force told Reuters by phone from Adamuz that the piece had been spotted by search teams using drones earlier in the week and had now been physically examined by investigators, adding: "We will look at it to determine what it is."

"Due to its size and weight, it has been left in the place it was found and has not yet been collected."