The narcotics officers were at their front door, but the three occupants in the flat refused to let them in.
It resulted in a stand-off that lasted about five hours, during which one of the occupants climbed onto the window ledge of the eighth-storey flat.
The drama, which began past 3pm, unfolded at Block 350, Anchorvale Road, in Sengkang yesterday.
A spokesman for the Central Narcotics Bureau (CNB) said its officers were at the flat as there were suspected drug activities going on in the one-room unit.
Both the Singapore Civil Defence Force (SCDF) and the police were later activated.
As a precautionary measure, SCDF officers, who arrived at about 3.30pm, inflated a safety life air pack at the bottom of the block.
They also deployed rescue nets from the back of a ninth-storey unit, directly above the unit the suspects were in.
When The New Paper arrived at the scene at 5.20pm, a crowd of about 15 people had gathered at a grass patch below the block.
Those we spoke to, however, said they did not see or hear any commotion from the eighth-storey unit before the SCDF deployed its equipment.
One of them, Ms Shirley Rodriguez, 41, a resident of the block, said she was shocked to look out of her window and see SCDF officers at work.
"I did not even know something was happening until my children told me," she said.
Another resident, who only wanted to be known only as Mr Hisyam, said: "I went downstairs because I saw SCDF (officers) from my window."
Residents told TNP they saw police officers carrying riot shields and other officers going up to the apartment at around 6.10pm.
At least six of these officers were seen in the common corridor talking to someone in the flat through the windows and the front door, they said.
Occasionally, the door would open slightly and the officers would raise their hands as they spoke.
Meanwhile, officers from the SCDF and the police were also on the seventh and ninth storeys. TNP understands that officers from the Special Operations Command Unit were there as well.
The stand-off finally came to an end at about 8.10pm, when officers entered the flat.
A 39-year-old man was later taken out of the flat on a stretcher. SCDF said he was taken to Khoo Teck Puat Hospital.
Two other suspects, a 44-year-old man and a 37-year-old woman, were arrested and taken downstairs at around 9pm.
A police spokesman said all three suspects were arrested for drug-related offences.
"The police are also investigating an alleged offence of criminal intimidation against the 44-year-old accused," the spokesman added.
All three are Singaporeans.
The spokesman added that they had relented and allowed the officers to enter their flat after police engagement.
Residents said that all the units in the block were rental flats, and that most of the residents had been living there for less than five months.
They added that there were some nights when arguing and shouting could be heard from the various units in the block.
Ms Shirley said: "I am sad that all these things had to happen to our new home."
This article was first published on July 22, 2015.
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