A shopping centre escalator in Hong Kong suddently reversed direction, sending shoppers tumbling at high speed.

The escalator in Langham Place shopping centre, Mong Kok, was full of people when it suddenly changed direction, injuring 18 people.

A witness said that the escalator travelled "twice as fast" in reverse.

A spokeswoman for Langham Place claimed the machine had passed a recent inspection, but that the firm was "highly concerned" and has asked the relevant contractor to investigate the incident.