Residents at a cluster of blocks in Bedok South Avenue 3 are worried that their area may become "the next Bukit Batok hill" if the growing number of rats there is left unchecked.
Many rodents have been spotted around blocks 69 to 72 in the past year. Some residents said they have seen swarms of 20 rats scampering around in a carpark at night.
In December, a hilly area near Bukit Batok MRT station was infested by rats. This was blamed on leftover scraps from the indiscriminate feeding of stray dogs. More than 300 rats there were killed by pest controllers over two weeks.
Bedok South residents who spoke to The Straits Times suggested several possible causes - a nearby garbage collection point and a food disposal area near a coffee shop in Block 69.
East Coast Town Council (ECTC) said it was alerted to the rise in rat numbers by conservancy workers and residents last week, and has since taken measures to control the pests.
Mr Adrian Theseira, managing director of Wipeout Pest Control Services, which is leading the extermination exercise, said it has found more than 30 rat burrows and nests across blocks 69 to 72.
As of Monday night, it caught 38 rodents using traps in areas such as drains and rubbish chutes. The rats caught were killed. Since last Thursday, pest controllers have also placed poison in rat burrows.
On Monday night, The Straits Times spotted more than 10 burrows, two live rats and a dead one on the pavement next to the coffee shop.
An ECTC spokesman said residents can expect to see rat carcasses in the area during the exercise, which will last until early next month. Residents are advised to call the town council so it can send workers to remove the carcasses.
She also urged residents to help control the rat population by eliminating food sources, possibly scraps left over from the feeding of stray cats and pigeons.
The National Environment Agency (NEA) said it received several complaints about rats around Block 70 late last month. Inspections found 16 burrows and rat droppings in a bin centre and two food shops, which have since been given warnings.
Its officers have spoken to the owners and occupiers of the shops on proper waste disposal.
NEA also said it is working with the town council to step up estate cleaning and maintenance of the rubbish chutes
The Straits Times understands that a metal disposal container was installed this year at the Food Park food court to improve its waste management. Before that, scraps went into pails without lids.
Mr John Teo, 70, who lives in Bedok South's Block 69, said the rat population grew in the last eight months. The taxi driver, who watches television with his friends at Food Park every night, added: "In the last two to three months, there are smaller ones appearing, which means they are breeding."
Another resident, Mr Tan Teck Chin, 47, said: "It's a bit uncomfortable to eat and see rats so near."