Eleven adults and two juveniles have been charged over a riot at a Pinjarra shopping centre.

A 78-year-old customer caught up in the melee on Wednesday suffered a mild heart attack and was taken to hospital.

Two shop assistants were also assaulted.

Police say rocks, bottles, bricks and star pickets were used during the fight.

Detectives this morning raided several properties and took 13 people into custody.