The 40-year-old appeared in Cairns Magistrate's Court yesterday on charges relating to the importation of 4kg of methamphetamine. She was remanded in custody until December.

Australian Customs and Border Protection Service (ACBPS) officers said they examined the woman's baggage at Cairns Airport on Saturday after a flight arrived from PNG.

Officers said they noticed anomalies in an X-ray of the accused woman's baggage and on further inspection, found three packages containing a clear crystalline substance.

Presumptive testing of the substance was positive for methamphetamine, with an initial weight of 4kg.

Police said further forensic testing would be undertaken to confirm the exact weight and purity of the substance.

The matter was referred to Australian Federal Police, who charged the woman with importing a commercial quantity of a border controlled drug.

The maximum penalty for the offence is life imprisonment and/or a fine of $1.27 million.