Singapore Customs seized 1.9 million packets of contraband cigarettes in the first nine months of this year, almost double the 1.03 million confiscated in the same period last year.
At this rate, the authority is on track for its biggest haul of illegal cigarettes in four years, exceeding the 2.3 million seized over the whole of 2010.
The year before that, 2.9 million packets were seized.
Duty collected from legal cigarettes in the first nine months of this year came to $721 million compared with $692 million in the same period last year - a 4.1 per cent spike.
This suggests that smokers are increasingly ditching contraband cigarettes for duty-paid cigarettes, said Customs in a media statement on Thursday.
The agency attributed the increase in cigarette seizures to stepped-up enforcement, and its collaboration with other law enforcement bodies in weeding out contraband cigarette smugglers, peddlers and buyers.
In a recent operation last month, Customs officers nabbed a 57-year-old Singaporean man in Ang Mo Kio after intercepting his van, which contained 2,500 cartons of duty-unpaid cigarettes.
Officers then began an islandwide hunt for a truck the suspect had rented.
A further 10,800 cartons of duty-unpaid cigarettes were found when they located the truck in Bukit Panjang on Oct 4.
In total, the 13,300 cartons of contraband cigarettes, which had a street value of more than $1.2 million, evaded over $1.02 million in duties and Goods and Services Tax (GST) - making it the year's fourth largest haul.
This year's biggest seizure came during an operation on Jan 23, when 18,000 cartons were discovered in a trailer at Jurong Port.
A further 3,227 cartons were found through follow-up operations over the next two days.
The total value of the cigarettes and the total duties and GST evaded exceeded $2 million and $1.8 million, respectively.
Singapore Customs' senior assistant director-general (Intelligence and Investigation) Lee Boon Chong said: "We will continue with our strong enforcement efforts to keep the smuggling, peddling and buying of contraband cigarettes in check."
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