Two people have been arrested in regional South Australia amid an investigation into the passing of counterfeit cash, police say.

SA Police said detectives from Kadina, on Yorke Peninsula, searched a home at nearby North Moonta on Tuesday, and that officers allegedly found more than 30 fake notes.

A man and a woman, aged 38 and 32 respectively, were arrested and charged with deception, police said.

Kadina police also allegedly found an imitation firearm and a machete at the property, and charged the man with possessing a prohibited weapon, and a firearm without a licence.

Earlier this month, police issued a warning about the circulation of fake money after two separate arrests and dozens of incidents in recent months .

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