Two people are expected to be charged.
Gang Crime Squad have seized illicit substances and drug paraphernalia during a search warrant in Kwinana on Thursday morning.
Officers executed a search warrant on Hutchins Way, where they located and seized a small quantity of cannabis, drug paraphernalia and steroids.
A 39-year-old man was arrested on an outstanding warrant and will be charged by summons with possessing cannabis and possessing a smoking implement.
A 20-year-old woman will be charged by summons with the same offences.
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