A radiographic scan inconsistency with what was declared in the permit documents prompted the authorities to perform a physical inspection on the consignment on Wednesday.
The 40-footer container at the Pasir Panjang Scanning Station was on trans-shipment and bound for the Keppel Free Trade Zone.
Upon inspection, Officers from the Immigration and Checkpoints Authority (ICA) found cigarettes packed in innocuous-looking brown boxes.
Stuffed in the boxes were 412,000 packets of duty-unpaid cigarettes, with an estimated street value of S$4.12 million.
It is their largest haul to date, of contraband cigarettes in five years with evaded duty to about S$2.9 million and GST evasion amount totalling S$275,000, amounting to about S$3.2 million.
Upon conviction, first time offenders can be fined up to 20 times the amount of duty evaded and be liable for a jail term not exceeding three years.
For second or subsequent convictions, offenders can be fined up to 40 times the amount of duty evaded and jailed for up to six years.
The offenders also face further fines based on the amount of GST evaded.
The conveyances or vehicles used in transporting the contraband will also be liable for forfeiture.
In a joint operation conducted with the Royal Malaysian Customs, a container load, declared in the manifest as hydraulic brakes, were 502,500 packets of cigarettes of assorted brands.
It was seized by Singapore Customs on April 25.
Among contraband smuggling items, duty-unpaid cigarettes lead with an increase of 45%.
About 19,000 cigarettes were seized in 2009, 27,000 in 2010 and already 1.29 million packets seized in 2011.
The number of cigarette offenders had increased by 30% to 25,787 offenders.
Singapore Customs noted that the offences were mostly committed by travellers who had brought in loose packets for personal consumption.
To create greater public awareness on the requirement to declare dutiable goods brought into Singapore, a series of media publicity to reach out to travellers had been launched by the agency in January this year.
More stringent checks and efforts by Singapore Customs, ICA and Police Force, had led to a five-year low record of 2.3 million packets of illegal cigarettes being seized last year, a fall of 21% from 2009.
The number of people caught buying illegal cigarettes had also dropped by 17% in 2010, registering a four-year low record, a likely indication that more smokers are turning away from illegal sources for their puffs.
Duties collected from cigarettes rose from S$861 million in 2009 to S$877 million a year later, another likely indication towards lesser demand for contraband cigarettes in the black market.
Officers from the Immigration and Checkpoints Authority (ICA) and Singapore Customs staking out at Bedok Industrial Park on Thursday March 24, 2011, became suspicious when they spotted a man leaving hastily in a taxi, right after unlocking the side doors of the truck.
They caught up with him and escorted him back to the truck.
The 46-year-old Singaporean was immediately arrested after unlocking one of the two parked Singapore-registered truck.
The storage area seemed to be loaded with just brown cement bags.
But hidden in these bags - and in similar bags in another nearby truck, ICA and Singapore Custom uncovered smuggled cigarettes of assorted brands.
Over 6,504 cartons and another 6,042 loose packets of contraband cigarettes, with a tax payable amount of S$545,700 were stashed in both parked truck.
The man carried the keys to both trucks that contained the contraband cigarettes.
The man was promised S$100 a day to unlock the truck to allow illegal peddlers, to retrieve the cigarettes.
If the man is a first-time offender, he can be fined up to 20 times the amount of duty evaded, and jailed a maximum of three years.