An American woman injured in last week's railway accident in the northwestern Spanish region of Galicia died Sunday, raising the death toll from the train wreck to 79, regional officials said.

The woman's identity was not released.

Citizens of Spain, Colombia, Mexico, Brazil, the Dominican Republic, Italy, France, Algeria and the United States were among those killed in last Wednesday's accident.

A total of 70 people were still hospitalized as of noon Sunday, officials said.

Twenty-two people, including two children, are listed in critical condition, while 48 others are in less serious condition, Galician regional government officials said.

People from seven countries - Spain, Argentina, Venezuela, Colombia, Peru, the United States and Britain - are among the injured.

The high-speed passenger train went off the tracks Wednesday along the route linking Madrid and the Atlantic coastal city of Ferrol.

The train involved in the accident entered service in 2012 and can go up to 250 kph (155 mph) on international rail networks and 220 kph (136 mph) on the Spanish high-speed rail system.

The signals on the stretch where the accident occurred were operating properly at the time of the derailment and the train had been inspected earlier in the day on Wednesday, Spanish railway operator Adif said.

Francisco Jose Garzon, the 52-year-old driver of the high-speed train, was released from the hospital Saturday and taken to a police station, where he is being held on suspicion of negligent homicide, Interior Minister Jorge Fernandez Diaz said.

Garzon invoked his right to remain silent when police sought to question him at the hospital.

Officials say excessive speed may be to blame for the crash, and Garzon apparently admitted last week that he was going at around 190 kph (118 mph) on a curve with a speed limit of 80 kph (about 50 mph).

"I derailed, what am I going to do, what am I going to do," Garzon, who has worked as a train operator since the 1990s, told the national government's representative in Galicia, where Santiago de Compostela is located. EFE