Fake drugs in the form of some 2.4 million pills and 470 liters of fluids with a $17,55,000 market value were intercepted, according to customs authorities estimates, the Efe news reported.
Guy Fong, head of customs at the intellectual property department, said the drugs were packaged to resemble those used to alleviate common diseases such as rheumatism.
According to the official, drug stores sold these medicines only to people they thought were "gullible or traders who came from the mainland."
"We believe they did not provide these kinds of medicines to average customers," Fong said.
"They would take a look at the profile of the customer. If they believed they (the customers) were not sharp enough or they believed they were mainland parallel import traders, they would recommend these counterfeit medicines to them," he added.
Some medicines were discounted by more than 50 per cent compared to genuine drugs, and packaged as if they were meant for export to underdeveloped countries.
As a part of the operation, customs officers raided several pharmacies in Sheung Shui, Yuen Long and Jordan neighbourhoods, as well as another three in an industrial building in Chai Wan, used to store and package the goods.
Fake cosmetics and skincare products were also among products confiscated during the operation.
Police said seven people including the mastermind of the operation were arrested.
( With inputs from IANS )