Five teenagers were among 85 people arrested in a major operation that ended on Saturday.
A 15-year-old boy was arrested for illegal moneylending activities, said a police spokesman.
The teenagers, including the oldest at 19, were arrested for drug, illegal moneylending activities and a vice-related offence.
The 41-hour operation that ended at 3am that day was spearheaded by officers from Jurong Police Division. The raid covered at least nine locations within the division, including Housing Board units and entertainment outlets.
The New Paper accompanied the law enforcement agencies as they raided three KTV lounges at Superbowl Jurong at Yuan Ching Road for vice-related activities.
It was already 12.30am on Saturday when TNP entered one of the KTV lounges. Police officers checked every corner, including the karaoke rooms, each about the size of an HDB bedroom.
A cacophony of voices could be heard, caterwauling off-key renditions of Mandopop hits. The guests were oblivious to the raid that was taking place within the same establishment.
At the end of the corridor was a spacious lounge that could comfortably seat about 100 people. Seated on the sofas were about 30 women. They were instructed to place their mobile phones and identification papers on the tables before them, and they silently complied. One of the women was a permanent resident, but most of them were work-permit holders.
One by one, the women were called to another part of the room where officers were seen scrutinising their particulars.
After that, each woman had her name written on a piece of masking tape which was then stuck across her chest.
About an hour later, some of them were led out of the KTV bar, straight into police vans downstairs.
Following the raid, some of the nightspot's customers abandoned their night of merrymaking and made their way to a nearby fast-food restaurant.
TNP spoke to one of them, who said he goes to the bar about once a month to "sing karaoke".
The 20-something man, who declined to be named, said: "I know that lots of pretty women work here, but I never engaged them.
"Most of the time, it's usually 'ah peks' (elderly men) who take them out."
Those who work nearby said they had noticed women dressed in sexy clothes streaming in and out of the KTV bars.
One in his 20s, who wished to remain anonymous, said: "I've never been inside any of these bars, and I don't intend to. But these women don't disturb anyone. I'm here to do my job and they do theirs. Who am I to judge?"
But the job they allegedly did is illegal.
At the KTV lounges, 36 women were arrested for keeping, managing and assisting in managing places where sex workers were assigned. The police said 28 are Vietnamese, seven are Chinese nationals and one is Thai.
Two men were also caught for drug-related offences.
Personnel from the Singapore Civil Defence Force, the Immigration and Checkpoints Authority and the Central Narcotics Bureau also took part in the operation.
In all, they arrested 85 people, including 53 women. The youngest of the 85 arrested was 15 and the oldest, 71.
This article was first published on June 30, 2014.
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