One man suffered a head injury and was arrested for affray and carrying a weapon. Police are hunting for another man, who fled after dropping a weapon.
A video posted on social media captures the chaotic scenes, as Boxing Day shoppers ran from the scene in panic. Some are seen leaping over the side of an escalator to escape. There were also images of two officers wearing stab vests leading a suspect away with handcuffs behind his back. One officer was holding a 2ft-long machete belonging to one of the suspects. Two knives were recovered at the scene.