Spain begins three days of mourning as train crash death toll reaches 69

Spain has begun three days of mourning after its second high-speed rail collision this year killed 69 people.

A minute of silence was observed across the country, including by lawmakers outside Parliament, rail workers and union leaders in Madrid's main train station.

Spain's Prime Minister Pedro Sanchez faces a general election in late November.

One of Europe's deadliest train disasters this century has raised fresh questions about safety on Spain's rail network after the transport minister said an "error" and "inexplicable circumstances" caused the crash.

During a visit to the crash site, Prime Minister Pedro Sanchez, who faces a general election on November 29, pledged to establish the cause of the crash.

"We are working day and night not only to support the victims' families, but also to establish every last detail of this tragedy and strengthen safety measures to ensure it never happens again," he said.

The collision happened in the central region of Castilla La Mancha on Wednesday morning when a train from state operator Renfe rear-ended a stationary train belonging to private Spanish company Iryo.

Emergency services combed through the wreckage overnight in search of victims on the key line that links Madrid with the southern city of Seville.

Sniffer dogs and thermal drones were deployed at the crash site a few kilometres from the village of Urda on Thursday to search for bodies, the regional government said.

The death toll was raised from 68 to 69, and 50 people remain in hospital.

A minute of silence was observed at midday on Thursday across the country, including by lawmakers outside Parliament, rail workers and union leaders in Madrid's main train station.

Flags flew at half-mast on public buildings in Spain, with official ceremonies and public events cancelled or scaled back.

On Wednesday transport Minister Oscar Puente, who faces calls to resign, said an automatic control system shut down on 69 kilometres of track, causing all trains on the stretch to be stopped, including the Renfe train.

But the control centre decided to "resume traffic in circumstances that, from our point of view, are inexplicable," Mr Puente said.

The Renfe train travelled 25 kilometres on the stretch before striking the the back of the Iryo train.

The control centre "had more than enough time to verify the error, and they did not fix it" he added.

Josimar Medina from Peru is holidaying in Spain with his girlfriend, and said he was sleeping on the Renfe train when "I woke up and I was in the air."

Pablo Mejia escaped with injuries to his head, telling AFP that a last-minute change of seat saved his life.

Wearing a bloodstained grey jumper and holding his tattered suitcase, he recounted "a very strong hit."

"A lot of people on the floor, on top of each other, seats ripped out, suitcases, a lot of chaos,

"I think I've been born again," Mr Meija said.

A school near the crash site in Urda is being used as a temporary support centre, for relatives to enquire about their loved ones.

Red Cross psychologist Carmen Garcia said "long and hard hours" were in store because "every person will manage it in their own way."

"We have people who are in shock, who haven't taken on board what has happened, angry people, sad, worried people. The grieving will be complicated," Ms Garcia said.

Jose Miguel Fernandez works as a parish priest in the area and joined emergency services in offering support to victims' families.

In January, two high-speed trains collided in the southern region of Andalusia, after one derailed and crossed onto the adjacent track, killing 46 people.

In its wake Spain's government faced heavy criticism over its management of the country's railways.

The investigation into the January incident is ongoing.

Train workers held a strike on Thursday that was planned before the crash, to demand the government carry out safety improvements to the rail services.

Unions say changes were promised after the first deadly collision in January.

Union leaders questioned the why the minister had placed blame on one controller, and criticised the leaking of the control room's conversations to the media.

"The focus should not be on if there was a human error, but rather what is wrong with the system," said Pepa Páez, the general secretary of the railway sector of CCOO, the largest trade union in Spain .

"What situations must be improved so that if there is a human error we don't find ourselves in this situation," he said.