A man will face court after more than 700 kilograms of Alprazolam, also known as Xanax, was found in storage unit in western Sydney.
The $12 million haul marks the largest single seizure of pharmaceutical drugs in NSW history, police said in a statement on Thursday.
A total of 722kg of the drug was uncovered during a search of a storage unit in Auburn on Sunday.
As part of the investigation, police stopped and searched a truck at Wagga Wagga, in the state's south, on Wednesday evening.
Officers allegedly located shopping bags containing almost $1 million in cash.
The 28-year-old male driver was charged with supplying a greater than large commercial quantity of a prohibited drug and knowingly dealing with the proceeds of crime.
He was refused bail and will appear before Wagga Wagga local court on Thursday.