The stepped-up checks for escaped Jemaah Islamiyah terrorist, Mas Selamat bin Kastari at the checkpoints have put physical strain on the officers from Singapore's Immigration & Checkpoints Authority (ICA) but their motivation and vigilance levels still run high.

During their stint of enhanced vigilance, officers detected two contraband smuggling cases in a span of less than four hours.

In one case, ICA managed to unveil the largest contraband smuggling of this year.

On the night of 25 March 2008, a Malaysia-registered lorry driven by a male Malaysian Malay accompanied by a female Malaysian Chinese arrived at the Cargo Complex of the Woodlands Checkpoint.

The lorry was declared to be conveying 'dustbin bags' and 'calcium carbonate'.

However, the ICA officer manning the radiographic scanner noticed anomalies in the scanned image of the cargo and alerted his colleagues to conduct further checks.

ICA officers uncovered the largest haul of tobacco for the year - nearly 430,000 sticks of contraband cigarettes.

The smugglers had attempted to throw the officers off track by layering the top tier with the declared consignment.

The ICA officers found the contrabands hidden beneath the top layer.

The 38-year-old driver and his 25-year-old companion denied knowledge of the exhibits found and the latter also claimed that she only accompanied the driver to Singapore for sightseeing.

The potential Customs duty and GST payable for the contrabands amount to about $151,000 and $13,500 respectively.

Another case also happened on the same day but earlier in the evening.

A Malaysia-registered car driven by a male Malaysian Chinese accompanied by a female Malaysian Chinese arrived at the Woodlands Checkpoint.

In the course of the check, an ICA officer observed the door panels of the vehicle to be heavier than usual and further sighted cigarettes hidden at the rear left panel of the boot.

The vehicle was sent for thorough checks and ICA officers uncovered cartons of contraband cigarettes hidden at both door panels and side skirting of the car.

A total of 366 cartons of cigarettes were found hidden in various parts of the vehicle including the bonnet, side panels of boot, seats, backrest, door panels, side skirting and undercarriage.

When interviewed, the subjects revealed that they were acquaintances.

The 21-year-old Malaysian driver admitted knowledge of the contrabands and claimed that he was promised employment and a cash sum of RM20 (S$8.67) if his delivery was successful.

On the other hand, his 18-year-old female companion denied knowledge of the exhibits found.

The Customs duty and GST involved amount to around $30,300 and $2,700 respectively.

Both cases have been referred to Singapore Customs for further investigations.

Upon conviction by the court, first time offenders can be fined up to a maximum of 20 times the amount of duty evaded. For second or subsequent convictions, offenders can be jailed for up to two years, as well as being fined. The offenders also face further fines based on the amount of GST evaded.

The enhanced security checks are critical to Singapore's security especially with the escape of Mas Selamat Kastari.

The ICA has tightened their security checks on passengers and vehicles at the checkpoints to prevent attempts to smuggle in undesirable persons, drugs, weapons, explosives and other contrabands.

The same methods of concealment used by contraband smugglers may be used by terrorists to smuggle arms and explosives to carry out attacks in Singapore.

ICA says they will put in every effort and continue to take the necessary measures to improve clearance efficiency as much as possible without compromising security.

ICA seeks your continued understanding and cooperation, and would like to advise against smuggling unlawful goods into Singapore.