SINGAPORE - A man drowned in Punggol Waterway during a police operation on Tuesday night (Nov 24).

No details have been released about the victim but residents at the nearby Punggol Parcvista development reported hearing shouting and seeing flashlights being shone by officers on the hills overlooking the park as people were chased out from the forested area.

Ms Eilene Poh, 28, who lives in Block 313C Sumang Link overlooking the park, said: "I saw men and women sitting on the slope of the hill with their hands restrained behind them."

She added that they appeared to be foreigners.

At about 11.15pm, police cordoned off a stretch of about 100m of the waterway and bystanders were told to move away.

Divers and other officers from the Singapore Civil Defence Force (SCDF) could be seen searching the waterway.

An SCDF spokesman said the body was recovered from the water at around 11.30pm and the man was pronounced dead on site by paramedics.

Police said 13 men and eight women were nabbed for willful trespass onto state land.

Chinese daily Lianhe Wanbao had previously reported vice activities in the area, involving foreign construction workers and women believed to be of Thai or Vietnamese origin, in February last year.

Investigations are ongoing.