Detectives and the Gang Crime Squad have charged two people in relation to the matter.
Around 9.40am on Thursday Police conducted a traffic stop of a vehicle in Pinjarra where they discovered illicit drugs were found on the male driver.
A further search of the vehicle was conducted and it will be further alleged that a number of firearm related items were located.
A search warrant was then executed at a residential premises in Beverley, south of Northam, where authorities located a large quantity of ammunition, firearm mechanisms& items consistent with the manufacture of firearms as well as prohibited drugs.
Northam Detectives have charged a 49-year-old man from Beverley two counts of unlicensed person possess firearm/ammunition, two counts of unlicensed manufacture of firearms/ammunition, one count of possess a prohibited drug (methyl amphetamine) and threats with intent influence.
They also charged a 51-year-old Beverley woman with one count of possessing cannabis and possess drug paraphernalia.
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