The U.S. State Department says one American is among the 80 people killed in yesterday's train derailment in Spain, and that five other Americans were hurt.

TV Journalists report from a vegetable plot near a train crash that killed at least 80 people in Spain (Pablo Blazquez Dominguez/Getty Images)

Meanwhile, Spain's government says two investigations have been launched into the cause of the crash near the Christian festival city of Santiago de Compostela in northwestern Spain. The regional government confirms that the train driver, who's hospitalized, is being questioned as a possible suspect, but that investigators are also looking at possible trouble with safety equipment.

According to eyewitness accounts and video of the crash, speed may have been a factor. The train was going so fast, its cars tumbled off the tracks like dominos. One witness says he saw the train "coming out of the bend at great speed and then there was a big noise."

An analysis of the video by The Associated Press indicates that the train was traveling at least 89 miles an hour, and possibly over 100 miles an hour. The speed limit in the area is 50 miles an hour.

(Copyright 2013 by The Associated Press. All Rights Reserved.)