SINGAPORE - Two Malaysian-registered buses - one with students on board - were caught smuggling cigarettes into Singapore last week, said the Immigration and Checkpoints Authority (ICA).

In the first case, 69 cartons and 112 packets of cigarettes were found on a school bus with six students on board.

They were on their way to school in Singapore at around 6.40am on Nov 6.

The bus driven by a 30-year-old Malaysian woman was intercepted at Woodlands Checkpoint.

The contraband cigarettes were hidden in the modified storage areas of both sides of the bus.

The second cache of duty-unpaid cigarettes were found in the rear luggage compartment of a bus.

At about 1am on Nov 9, an empty bus driven by a 19-year-old Malaysian man was directed for further checks at Tuas Checkpoint.

ICA officers seized 1,850 cartons and 499 packets of cigarettes from the bus.

The total duty and Goods and Services Tax evaded for the two cases exceed $153,650 and $14,660 respectively.

The subjects, contraband cigarettes and vehicles for both cases were handed over to the Singapore Customs for investigations.

The 30-year-old Malaysian woman was sentenced to three months' jail on Wednesday (Nov 11). Investigations are ongoing for the 19-year-old man.

The ICA noted in a statement that the same method of concealment used by smugglers may be used by terrorists to smuggle arms and explosives to carry out attacks in Singapore.

It said security checks are critical to Singapore's security and that it will continue to conduct security checks at the checkpoints to prevent smuggling.