An alleged multimillion-dollar drug importation scheme has been undone after police narrowed in on who they described as a “trusted insider” in Sydney.

Strike Force Aulic, including officers from NSW Police, Australian Federal Police, Australian Border Force, NSW Crime Commission, Australian Criminal Intelligence Commission, Australian Transactions Reports and Analysis Centre, and Australian Taxation Office, was established in 2023.

It was set up to investigate the alleged importation and supply of large quantities of illegal drugs and illicit tobacco by Gurvinder Singh, 42, and his associates.

Police allege Singh told others of his abilities to circumvent border controls and had been using a freight company in Punchbowl to facilitate the imports.

In July last year, police found more than 280kg of liquid methamphetamine in an industrial cooler imported from Vancouver, Canada, allegedly organised by Singh.

On August 5 that year, two men, aged 43 and 31, were allegedly seen accessing the cooler and preparing to extract the liquid meth at a location in Riverstone.

Police arrested the 43-year-old man at a fast-food restaurant in Londonderry about 7pm that same day.

Officers searched an address in the same suburb and allegedly found gel blasters, a meth cookbook, and other items used to manufacture and supply drugs.

The man was charged with 17 offences, including commercial-level drug possession and weapons charges.

He was refused bail and appeared in court on August 6 last year.

During a search warrant in Box Hill that same day, investigators arrested a 31-year-old man.

He was charged with being part of a criminal group and granted bail.

He appeared in court on September 4 last year.

Police continued to investigate Singh, who allegedly continued to use the freight forwarding company to import three separate consignments, containing more than 20 million cigarettes, from the United Arab Emirates.

In May, investigators discovered he was allegedly planning to import 50kg of cocaine in a shipping container from Panama, concealed in cement bags.

Police alleged Singh sought help from two men who flew in from Canada to retrieve the cocaine from the cement bags and onward supply it to organised crime groups in NSW.

About 2pm on Friday, investigators arrested four men in Wetherill Park and executed six search warrants in Moorebank, Punchbowl, Smithfield, Doonside and Mount Annan.

Singh was charged with multiple offences related to drugs, proceeds of crime, and directing a criminal group.

He remains in custody and will next appear in court on July 31.

Another 42-year-old man was charged with attempted drug importation and criminal group participation.

He was refused bail and will next appear in court on June 5.

Two Canadian nationals, aged 24 and 31, were both charged with attempted drug possession and criminal group participation.

They were refused bail and will appear in court on June 13.

Police seized a number of items during the searches, including 243 boxes allegedly containing tobacco, at two storage facilities in Moorebank.

A 36-year-old man was arrested at Sydney Airport about 6.50pm on Saturday.

He was charged with illicit tobacco importation and criminal group participation.

He was refused bail and appeared in court yesterday.

A total of seven men are behind bars, but police say the investigation remains ongoing.