The heat is on for the Bukit Batok rats which survived the earlier poison and traps.
Pest controllers are monitoring the area near the Bukit Batok MRT station with 20 infrared cameras after starting Stage 2 of operations to get rid of a rat infestation there on Thursday.
Highlighted by a resident last week, the infestation was deemed by pest controllers to be "under control" after Stage 1.
The aim now is to eliminate the survivors and ensure they do not migrate to other areas.
Pest controllers will also conduct surveillance with binoculars from high vantage points such as multi-storey carparks in this second phase, which is expected to last a fortnight.
Stage 1, which involved laying traps and treating rat burrows with chemicals, was completed on Wednesday, said Star Pest Control manager Bernard Chan.
An overnight assessment of the area for signs of rats from Tuesday morning to Wednesday found only a few remaining rats, he said.
"Those which survived are very alert now and will be in hiding, so we need to quieten down now through Phase 2 and wait for them to resurface," he said.
Meanwhile, in a letter published in The Straits Times' Forum page today, the Society for the Prevention of Cruelty to Animals refuted the notion that "community dogs" there are responsible for the rat infestation. Its executive director Corinne Fong said she strongly disagreed with the suggestion by Forum contributor George Wong Seow Choon to "trap and remove all the stray dogs in the area". Instead, she urged tolerance of these animals.