Immigration & Checkpoints Authority (ICA) officers seized some 2,387 cartons of contraband cigarettes and 697 bundles of chewing tobacco over the weekend.
The items, with a total estimated customs duty of about $213,800 and GST of about $18,970, were confiscated from a total of six men, four cars, a motorcycle and a truck,
The suspects were nabbed at Singapore's two land checkpoints in Tuas and Woodlands, said the ICA in a statement on Tuesday.
ICA Officers at Woodlands Checkpoint also uncovered a sugar glider hidden in a toothpaste box kept and carried in an inner pocket of a motorcyclist on Jan 12.
The case and the 33-year-old Malaysian rider were handed over to the Agri-Food & Veterinary Authority (AVA) for investigations.
As sugar gliders - small squirrel and possum-like animals - are not approved pets in Singapore and should not be imported or kept by private owners, the AVA later issued the offender a compound fine and a stern warning letter.
The sugar glider was sent to the Singapore Zoo.