A dual citizen is facing court after a fluid was spotted oozing from his suitcase after flying back home to Australia.

The Australian-Afghan man, 47, was stopped after getting off an international flight at Adelaide Airport on Tuesday.

“A black fluid (was) oozing from the handle of the man’s suitcase,” Australian Federal Police (AFP) said on Wednesday.

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A test of the substance came back positive for heroin and 500g of the illicit drug was allegedly removed from the bag, police said.

The South Australian man was charged with one count of importing a marketable quantity of a border-controlled substance.

He now faces a maximum of 25 years in jail if found guilty.

The 47-year-old appeared in Adelaide Magistrates Court on Wednesday and is set to reappear in court on September 23.

AFP said the man was “targeted” for a full bag search using “officer intuition” but the discovery was “not based on luck”.

“This isn’t an isolated case, these successes happen across our airports every week,” ABF Superintendent Jody Griswood said.

“ABF officers at the border are highly trained, experienced and alert. They know exactly what to look for when selecting travellers and their baggage for further examination.”

AFP Detective Acting Superintendent Simon Lalic said criminals trafficking drugs are “motivated by greed” and must be stopped at all levels.

“They have no regard for the significant harmful impacts these illicit drugs have on our community.”