Eleven people were arrested for shop theft in one week at a supermarket in Tampines, police said.
All the thefts, which took place in the first week of December, were at the self-checkout counters at the supermarket on Tampines North Drive 2.
The suspects are believed to have put unscanned items into plastic bags containing other scanned items.
Police reminded the public that shop theft is a "serious offence punishable with a jail term of up to seven years and a fine".
They will continue to work closely with the retailers including supermarkets to ensure such acts do not go undetected, police said.