More questions have been raised about rail travel safety on Friday as death toll climbed to 80 in one of Spain's deadliest train crash.

A video shown on Spanish TV shows that the accident appeared to be caused by excessive speed as the train went into a curve and hurled off the tracks at around 190 km an hour.

The maximum speed limit for the road stretch is 80 km an hour.

As of Friday, the railroad disaster has killed at least 80 people and 95 others were hospitalized, with 35 in critical condition, according to the government of Santiago de Compostela, where the derailment occurred Wednesday evening.

The crash is the deadliest rail accident since 1944 when hundreds were killed in a train collision.

Santiago de Compostela canceled a major religious festival of St. James on Thursday, one of the Europe's biggest Christian festivals.

A judge in the Spain's northwestern city has been assigned to investigate the accident, ordering police to question the train's driver.

The driver, a veteran of over 30 years' experience, was reported to have admitted of traveling at 190 km per hour. He passed the alcohol test and is currently receiving hospital treatment under police supervision.

The driver once made jokes on his Facebook page about breaking the speed limit.

Meanwhile, the high-speed trains have been equipped with an automatic speed control system called the European Rail Traffic Management System (ERTMS), but the system was not implemented 4 km before Santiago de Compostela, which is a transition zone between the high-speed line and a conventional line.

But another security system ADFA-200, which controls speed signals on the track, was implemented at the section of the tracks where the tragedy happened.

The judge, who has got the train's black box containing recordings of all cabin information, is investigating whether the driver ignore the signals or the system failed to kick in.

Spain on Thursday declared a three-day mourning for the victims of the crash and a minute's silence was observed at midday in all the public administrations, the Congress and Senate, as well as the offices of the political parties.

King Juan Carlos and Queen Sofia of Spain also visited the victims in Santiago de Compostela Thursday evening.