THE full horror of one of Spain's worst rail disasters has been revealed after CCTV footage was released that captured the moment the train came off the rails and struck a wall.

At least 80 people died and more than 30, including children, were critically injured in the crash.

The footage showed the Madrid to Ferrol express hurtling towards the camera before the carriages skidded off as it pulled into the main station near the north-west city of Santiago de Compostela.

It emerged one of the drivers allegedly joked on Facebook on a previous occasion about speeding past police, according to reports.

Early investigations into the crash have suggested the train was travelling at 118mph, more than twice the speed limit, when it derailed heading into the sharp curve.

One Briton has been confirmed by the Foreign Office to be among the 168 injured passengers.

As the country mourned, ­Spanish media named one of the train's drivers as Francisco Jose Garzon Amo and reported boasts he allegedly posted on Facebook about how fast he was driving a train in 2012.

The 52-year-old, who together with a second driver survived the crash and is being treated in hospital for minor injuries, is now reportedly under investigation.

He allegedly posted a picture of a train speedometer at 200kmh (124mph).

He is alleged to have wrote in March 2012: "What a blast it would be to go parallel with the Guardia Civil (Spanish police) and go past them triggering the radar.

"Haha what a fine for Renfe (the Spanish train operator) haha."

One of the two drivers at the helm of the train realised what was about to happen before the crash.

He made a desperate call to Renfe ahead of taking the bend, saying: "I'm going at 190kmh, I'm going to derail."

In a second call to Renfe after the accident, he explained that he was trapped in the train's loco.

He is reported to have said at the time: "We are human, we are human.

"I hope there are no dead because they would fall on my conscience."

Mr Garzon Amo is expected to give evidence to a judge with access to the train's data recording black box.

Many of those on the Madrid to Ferrol service would have been pilgrims travelling to today's St James's Day festivities, Santiago's festival to celebrate the disciple of Jesus whose remains are said to rest in a shrine.

He said: "For a native of ­Santiago, like me, this is the saddest day."

He added that judicial ­authorities and Spain's public works ministry had launched parallel investigations into what caused the crash.

Spanish officials said the speed limit on the section of track where the accident happened was 50mph.

Professor Roger Kemp, a Fellow of the Royal Academy of ­Engineering, said: "The big question is why the train was (reportedly) running at more than twice the speed limit.

"As the driver was leaving the high-speed line to join a much slower route before entering the station, there must have been at least prominent visual warnings to reduce speed, if not audible warnings and an electronic speed supervision system."

Alberto Nunez Feijoo, president of the regional government of Galicia, described the scene as "Dante-esque".

The crash is the worst Spain has experienced since a three-train accident in a tunnel in the ­northern Leon province back in 1944.

Due to heavy censorship which was in place at the time, the exact death toll for the Torre del Bierzo disaster has never been established.

The official figure was given as 78 dead, but it is thought that as many as 250 may actually have been killed.

In 1972 an express train collided head-on with a local train on the outskirts of Seville in the south west of the country.

A total of 77 people died in that incident.