Two technicians have been arrested after a Hong Kong escalator suddenly shifted into reverse at high speed, injuring 18 people.

Local news reports that one of the shoppers the Mong Kok’s Langham Place complex is in serious condition with a head injury after the escalator changed direction and accelerated without warning.

“It was so sudden that people couldn’t respond in time ... more than 10 people piled up near the base of the escalator,” shopper Lau Kit-ying Lau told the South China Morning Post.

The escalator reportedly passed a safety inspection just last week.

Local media reports that the two elevator technicians are charged with “perverting the course of justice.”

“I was going up the escalator, and it was two times faster than normal,” one shopper told The Morning Post.

“I heard people screaming ... the escalator was going down but the speed accelerated,” said the woman, whose leg was injured. “People started to panic ... and some fell down.”

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