Ten people have been injured after being sprayed with a homemade chilli spray during an attack in a Costco store.

Customers at the Somerset branch had to have medical treatment at the scene after the nightmare unfolded last night.

The liquid, which was unknown at the time, is extremely painful and Costco staff offered first aid to injured customers until the ambulance service arrived.

Police swooped and arrested a teenage boy on suspicion of ‘attempting to cause grievous bodily harm and administering a noxious substance.’

Ten people , including the boy, said their eyes and skin were stinging or itchy.  

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