Three other men were also arrested on Tuesday as part of the alleged syndicate. The arrests - as part of an ongoing investigation into corruption at Customs - relate to four separate importations of the drug, which is used to make ''ice'', in March and June 2012.

The arrests came as 15 search warrants were carried out across Sydney.

Further arrests are expected.

AFP Commissioner Tony Negus told reporters in Canberra that the customs officers conspired with a baggage handler, who is accused of removing suitcases of the drug from the back of the plane to avoid its detection in the baggage hall.

It will be alleged that the officers - one of whom was a supervisor - ''directed resources'' and monitored the CCTV footage to allow the importation to take place.

''The fact that a supervisor was involved in this process is of certainly concern,'' Commissioner Negus said.

The customs officers, who worked at Sydney Airport, include a 40-year old Kingsgrove man and a 38-year-old Blacktown man.

Also arrested were a 29-year-old Petersham man, who was a former baggage handler, and a 30-year-old Earlwood man. Both are alleged to be associated with the customs officers and co-conspirators.

The fifth man was a 35-year-old Oxley Park man and the brother of one of the officers. He will be charged with dealing with the proceeds of crime.

The others will likely be charged with a range of offences, including abuse of public office, conspiracy to import commercial amounts of precursor chemicals and giving and receiving bribes.

The 40 kilograms of pseudoephedrine seized in the final importation in June had the potential to make an estimated $9.5 million worth of ice.

The total number of those arrested as part of the investigation is now up to 17. This includes four customs officers and one from Australian Quarantine and Inspection Service, three others and nine drug couriers.

‘‘I’d like to stress that ... this is not the end of the matter,’’ Commissioner Negus said.