A traveller arriving in Australia from Indonesia has been hit with an almost US$2,000 fine after border guards detected two McMuffins and a ham croissant secretly squirrelled away in their backpack.

Biosecurity detector dog Zinta sniffed out the egg-and-meat contraband at Darwin Airport prompting an eye-watering fine, officials said Monday.

"This will be the most expensive Maccas meal this passenger ever has," said Australian agriculture minister Murray Watt.

Australia has hyper-stringent biosecurity laws designed to protect the country's large agriculture industry from imported pests and diseases.

Authorities are currently on high alert after an outbreak of Foot and Mouth Disease in Indonesia, with all meat imports from that country undergoing screening.

The disease poses no risk to humans but is a severe, highly contagious viral disease of livestock.

At Aus$2,664, the fine was equivalent to the cost of 567 sausage and egg McMuffins in Sydney, or several return flights to Bali.

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