Galicia, Spain: At least 78 people have been killed in the passenger train derailment in north-western Spain on Wednesday.
More than 140 were hurt, 20 seriously, after all eight carriages of the Madrid to Ferrol train came off the tracks near Santiago de Compostela.
Media reports say the train may have been travelling at more than twice the speed limit around a curve.
It is the worst train crash in Spain since 1944. Seven days of mourning have been declared in the Galicia region.
Prime Minister Mariano Rajoy, who was born in Santiago de Compostela, has arrived at the scene of the accident.
"I want to express my affection and solidarity with the victims of the terrible train accident in Santiago," Mr Rajoy said earlier.
The black box of the train is now with the judge in charge of the investigation.
The president of railway firm Renfe, Julio Gomez Pomar, has said the train in the crash had no technical problems.
"The train had passed an inspection that same morning. Those trains are inspected every 7,500km... Its maintenance record was perfect," he told Spanish radio.
Spain generally has a relatively good record in terms of rail safety, says the BBC's Tom Burridge in Madrid.
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This is a country which has invested huge amounts of money in its rail network, he says.
Renfe said the train came off the tracks on a bend about 3 or 4km (2-2.5 miles) from Santiago de Compostela station at 20:41 local time (18:41 GMT) on Wednesday.
It was on the express route between the capital, Madrid, and the ship-building city of Ferrol on the Galician coast, with 218 passengers on board - in addition to a unknown number of crew members.
Firefighter Jaime Tizon, one of the first to reach the site of the crash, described the scene as "hell".
"I'm coming from hell, I couldn't tell you if the engine was on fire, or one of the carriages or what..." he told ABC after dragging the injured and bodies from the train.
Earlier, the leader of the regional government Alberto Nunez Feijoo described it as "a Dante-esque scene", in comments to Spanish radio.
One witness, Ricardo Montesco, described how the train carriages "piled on top of one another" after the train hit a curve.
"A lot of people were squashed on the bottom. We tried to squeeze out of the bottom of the wagons to get out and we realised the train was burning...I was in the second wagon and there was fire. I saw corpses," he told Spanish Cadena Ser radio station.
Several eyewitnesses described the train travelling very fast before it derailed.