THROW litter like tissue paper and cigarette butts out of your flat's window and you may be nabbed on camera.
The National Environment Agency (NEA) has been ramping up its use of electronic eyes to catch high-rise litterbugs.
Now, it wants to continue the practice and hire a contractor to deploy high-definition cameras paired with video analytics to catch offenders in the act.
According to tender documents seen by The Straits Times, the cameras will be deployed temporarily to monitor housing units with suspected litterbugs.
The NEA estimated that there will be an average of 70 to 110 deployments each month, and about 1,080 a year, for the next two years.
Last year, the agency received 2,500 cases of feedback about high-rise littering, up from 1,600 in 2013.
It took action against offenders 206 times last year, compared with 458 times in 2013.
The NEA has already been using surveillance cameras in areas where complaints about high-rise littering persist. Last year, cameras were deployed at 600 locations, compared with about 500 places in 2013.
In January, a smoker who repeatedly chucked his cigarette butts out of his flat window was fined a record $19,800 and sentenced to five hours of corrective work, after he was nabbed with the help of surveillance cameras.
The new camera deployments will be at public housing estates and other locations, and the NEA said they should be able to help it identify perpetrators both during the day and in low-light conditions.
If this cannot be achieved, the system should at least be able to tell the agency which unit in an HDB block the high-rise litter came from, it said.
The tamper-proof cameras will be able to be mounted on rooftops, along common corridors of residential buildings, and at staircase landings, multi-storey carparks and other locations.
They will be able to record even the littering of small items like cigarette butts and tissue paper, and video analytic software will trigger an alert when such litter is captured by the cameras.
The NEA said the video clips might be submitted to court as prosecution evidence. Video or images that do not show any littering will be destroyed after three months.
Public Hygiene Council chairman Liak Teng Lit said the rise in feedback showed that people are becoming more vocal about such littering. He said: "In some of the cases, people have been putting up with the littering for months.
"This technology will help the NEA do its job, especially against the serial litterbugs, more efficiently."