Problems with a cable likely caused a Lisbon funicular railway popular with tourists to hurtle down a hill, killing at least 16 people and injuring another 22 when it crashed into a building, according to a preliminary report.
The yellow tram-like carriage, which carries people up and down a steep hillside in the Portuguese capital, hit a building after leaving the track on Wednesday, just metres from its twin at the bottom of a steep hill.
Portugal's Office for Air and Rail Accident Investigations on Saturday released its first investigative report into the crash.
The report said the cabins had travelled "not more than about six meters" when they "suddenly lost the balancing force provided by the cable connecting them."
"Cabin No. 2 suddenly reversed, its movement halting approximately 10 meters beyond due to its partial excursion past the end of the track and the burial of the underside of the trambolho (trolley) at the end of the cable trench," it added.
"Cabin No. 1, at the top of Calcada da Gloria, continued its downward movement, increasing its speed.
The report added: "The cabin's brakeman immediately applied the pneumatic brake and the hand brake to try to halt the movement. These actions had no effect in stopping or reducing the cabin's speed, and it continued accelerating down the slope."
The report added an examination of the wreckage showed "the connecting cable had given way" at the attachment point to the cabin at the top of the hill.
A final report will be published later.

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