This stretch of the Rail Corridor near Sungei Kadut Avenue used to be "off-limits" in the evenings.
Residents from a nearby Choa Chu Kang North housing board estate had previously reported being harassed by unknown men and sexily dressed women whenever they jogged or cycled there.
At night, contraband cigarette peddlers and pimps from a "jungle brothel" in the area had taken advantage of the tall vegetation to hide their illegal activities.
Today, the situation has changed.
The illicit activities seem to have stopped, said three Choa Chu Kang North residents, who jog there, to The Sunday Times. Two of them attributed the disappearance to a lone surveillance camera there.
Said Mr Adrian Sim, 35: "Ever since the tall grass began to be mowed every few months, the women and cigarette peddlers had nowhere to hide. So they left."
The solar-powered camera is located roughly 80m from the closest road.
"I don't think they'll dare return when the camera's in place," added Mr Sim. "It has been quiet since I first noticed the camera about one year ago."
Another jogger, Mr Thiru M., 44, said the roughly 1.5km-long path is used by workers to get to Yew Tee MRT station from Sungei Kadut Avenue. Mr Thiru, a logistics manager, said the Rail Corridor now feels "a lot cleaner and safer".
Now, more people can be seen walking or cycling there each evening.
In the past, empty cigarette cartons littered the ground, along with soiled condoms and tissue paper.
The Sunday Times has learnt that the surveillance camera belongs to Singapore grid operator SP Group. The newspaper understands that the CCTV camera was deployed to monitor SP Group's assets.
A security executive, who gave his name only as Mr Quak, said it did not matter whether the camera had been deployed to monitor illegal activities or property.
Mr Quak, in his 40s, said: "In the end, the camera had the unintended effect of spooking the culprits. It's human nature not to be caught on camera doing illegal things."
Yet, about a kilometre away at Yew Tee Industrial Estate, contraband cigarette peddlers seemed unfazed by the presence of four police security cameras placed at the entrance of the estate and close to a fenceline separating the Rail Corridor and the estate.
The area has been a hot spot for the sale of contraband cigarettes in the last decade.
In the last seven months, it was reported that about 20 people had been arrested for peddling illegal smokes in Singapore, and immigration and Customs-related offences.
The authorities had seized 181 cartons of duty unpaid cigarettes worth around $20,000.
A manager at a Bangladeshi- owned supermarket at the industrial estate has seen regular raids by the authorities.
The man, who gave his name only as Shameem, told The Sunday Times: "Once in a while I see police come and chase people."
Two shop owners had suggested installing floodlights and deploying guards there.
Last week, The Sunday Times observed 10 men standing in the dark behind a fence, roughly 10m away from the police cameras.
Showing the types of cigarettes he had inside a red plastic bag, one of them said in Bahasa Indonesia: "The cheapest I can sell you is $7 for a packet (of cigarettes). You want?"
The relatively high price indicated a shortage in supply of the contraband cigarettes at Yew Tee. A year ago, each packet was sold there for less than $6.
Singapore Customs 2016 enforcement results showed there were 2.82 million packets of contraband cigarettes seized that year in 34 inter-agency joint operations islandwide. Roughly $1.07 billion in revenue was collected from the sale of duty-paid cigarettes last year. Some 437 peddlers were arrested.
