SANTIAGO DE COMPOSTELA, SPAIN — The train races into view, and in the space of a heartbeat, the cars derail and crash into a wall of concrete, flipping onto their sides and skidding along the track with terrifying speed and force.
Security footage shows the horror of the moment an express train derailed as it hurtled around a curve in northwestern Spain on Wednesday. A spokeswoman for the Spanish government in the Galicia region, speaking on routine condition of anonymity, confirmed 80 people have died in the crash.
One U.S. citizen is among the dead, according to Deputy State Department spokeswoman Marie Harf. At least five U.S. citizens were also injured, she added.
Flames burst out of one train car as another car was snapped in half after the crash. Rescue crews and fellow passengers pulled bodies through broken windows and pried open doors as stunned survivors looked on.
Investigations into the cause of the crash continue, but suggestions that the train was traveling too fast appear to be gaining weight.
The train driver is being questioned by police and is under formal investigation, said Maria Pardo Rios, a spokeswoman for the Galicia regional supreme court. "He is not being charged by a judge at the moment -- it is all at a police level," she said.
Ninety-five of the 178 injured are still hospitalized, the local government's official Twitter account said. Thirty-two adults and four children are in critical condition.
Most of the deaths happened at the scene, Rios said. In Spain, judges typically record deaths that take place outside of hospitals.
Judicial teams are still at the crash site and expect to find more bodies, she told CNN on Thursday morning.
Interim charge d'affaires Luis G. Moreno at the embassy said it was in touch "with families of some injured American citizens."
"We are deeply shocked by the news of last night's train crash in Galicia. Our hearts and prayers are with the friends and families of the victims," he said Thursday.
UK Foreign Secretary William Hague said one British citizen was injured.
The crash came on the eve of a public holiday held to mark the region's saint's day. Local officials canceled festivities planned for Wednesday night and Thursday across Galicia.
Train's speed questioned
The state railway, Renfe, said the train crashed on a curve several kilometers from the train station in the city of Santiago de Compostela, a popular tourist destination.
The train was nearing the end of a six-hour trip from Madrid to the town of Ferrol in northwest Spain when it derailed at 8:41 p.m. Wednesday, the railway said.
It was unclear how fast the train was traveling when it crashed. It was capable of going up to 250 kilometers per hour (155 mph), said Julio Hermida, a spokesman for the state railway.
The driver, who suffered minor injuries, told police the train had entered the bend too fast, TVE reported.
The driver has worked for the company for the last 30 years, a spokesman for the railway confirmed to CNN. In 2000, the driver started working as a train driver assistant, and in 2003 began working as a train driver, a job the driver has held since.
Rafael Catala, secretary of state for transport and housing, told Spanish radio network Cadena SER that the "tragedy appears to be linked to the train going too fast," but that the reasons for that are not yet known.
Spanish news agency Efe and national daily El Pais cited sources within the investigation as saying that the driver had said the train was going at about 190 kilometers per hour, and that the limit on that curve was 80 kilometers per hour (50 mph.)
The president of Renfe, Julio Gomez-Pomar, told radio station COPE on Thursday that the train had undergone a routine inspection that same morning.
"The train did not have an operating problem," he said. "The maintenance and control record of the train was perfect."
Alberto Nunez Feijoo, head of the regional government in Galicia, declared seven days of mourning in the region for victims of the tragedy.
In a speech, he said "all of the community cries about the tragedy that we are living, we cry for the victims, we cry for the unease and sadness of the families."
Spanish Prime Minister Mariano Rajoy viewed the scene of devastation Thursday morning and visited some of the hospitalized crash victims.
Rajoy, who is from the area, told a news conference there was a "huge challenge" ahead, not least in identifying all those killed and informing their families, and he praised the response of everyone who has helped after the crash.
Two investigations are under way, he said, adding, "We want to establish what happened."
Rajoy declared three days of national mourning to honor the victims of the crash.
The prime minister came under fire in Spanish media after a condolences message for the train crash victims posted by his office late Wednesday included a paragraph apparently "copied and pasted" from a statement previously sent to victims of an earthquake in Gansu, China.
''I would like to express my deepest condolences for the loss of human lives and the material damage from the earthquake that has occurred in Gansu has caused," the note said.
Spain's King Juan Carlos and Queen Sofia are to visit Santiago de Compostela on Thursday. A spokesman for the royals said the couple will visit the Hospital Clinico of Santiago de Compostela just after 12:30 p.m. ET, or 6:30 p.m. local time. The king may speak after the visit, the spokesman said.
Earlier, the king said the incident had saddened the country and the international community. He sent a message to the victims and their families conveying "the deepest love and all the solidarity from the Royal Family, and from the whole nation."
The royal family has canceled all events scheduled for the day out of respect for the day of mourning, the royal household told CNN.
A passenger who got off at the last stop before the train derailed told the broadcaster it was packed with people at the time.
Residents who lived near the tracks told the Voz de Galicia newspaper that they heard a thunderous bang when the train crashed. Many of them rushed to the area with blankets and bottled water for the injured, the newspaper reported.
"The train had broken in half. Some pieces were on top, some pieces were on the bottom," said Ivette Rubiera Cabrera of Florida, who caught a glimpse of the wreckage while on a family vacation in Spain and sent photos to CNN's iReport.
"It was quite shocking," she said. "We had never seen anything like that. We had just been on the train last week."
Oscar Mateos told the El Pais newspaper that he saw fellow passengers thrown to the floor, then tossed from one side of the train to the other.
"Help came in five minutes, but that time became an eternity," he said. "I helped people get out with broken legs and many bruises."
Alen Perez, 16, said he had been walking nearby and saw passengers helping each other out of the train.
Emergency vehicles swarmed the scene. There were several bodies on the ground, he said.
Photos he took of the crash site showed mangled pieces of a train car and black smoke billowing out of the wreckage.
Investigators are looking at all possible causes of the crash, a senior aide to the prime minister said Wednesday.
Renfe's spokesman said he did not know how many crew members were aboard the train when it crashed. Normally, there would be at least five crew members on a train like that, he said.
Officials appealed for blood donations just after the crash but on Thursday said the short-term needs were met.
Herman Van Rompuy, president of the European Council, expressed condolences from the European Union.
Pope Francis, who is on a visit to Brazil for World Youth Day, sent a telegram to the bishop of Santiago de Compostela, Julian Barrio Barrio, offering his support and prayers for all those affected by the tragedy.