Escalator chain reactions can happen when one person stumbles and falls, or when people use a non-working escalator as a staircase and it suddenly starts moving again. In Hong Kong over the weekend, a 150-foot mall escalator abruptly reversed direction and flung screaming shoppers to the ground, injuring 18 of them.

Of course there’s video, from multiple angles, because this was a terrifying event that happened in a public place in 2017. One mall-goer happened to be taking video of the escalator before the mayhem started.

The escalator involved in this incident also happens to be massive, carrying shoppers from the fourth floor to the eighth floor of the mall at Langham Place.

To get an idea of how quickly the steps were moving, compare the speed of the escalator on the right to the malfunctioning one of the left.

“I was going up the escalator, and it was two times faster than normal,” one woman who injured her leg in the incident told the South China Morning Post.

Here’s a video taken from the ground at the bottom of the escalator, where you can hear the passengers screaming:

Two mechanics who work for the Otis Elevator Company were arrested in the Langham Place incident, accused of tampering with it in a way that caused the escalator to change direction suddenly and speed up.

According to the South China Morning Post, a total of 18 passengers were injured, including one man who was hospitalized with a head injury.

If don’t find the prospect of an escalator suddenly speeding up terrifying yet, here’s a similar pileup of horror that took place after a Philadelphia Flyers game last year, where an escalator malfunction made the machinery speed up, dumping passengers at the bottom. It didn’t change direction.

(via Gizmodo)

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