Three people have been arrested in connection with drug-related offences and a total of 3,720g of heroin, 813g of "Ice", 2,934g of cannabis and one Erimin-5 tablet were seized after an operation by the Central Narcotics Bureau (CNB) on Tuesday.

The CNB estimated the value of the drugs seized at $401,000.

The first suspect, a 24-year-old Singaporean man, was arrested following a raid on a residential unit in Edgedale Plains in Punggol on Tuesday evening, said a CNB statement yesterday. The man, who was the occupant of the unit, refused entry to CNB officers and tried to climb out the window on the 17th storey of the block.

CNB officers pulled him back into the unit and subsequently found six packets containing about 776g of "Ice" and two blocks of cannabis weighing a total of 1,914g.

The two other suspects - a Singaporean woman, 28, and a Malaysian man, 32 - were arrested in the vicinity of Balestier Road. Both were escorted to their nearby hotel room where a search found 3,720g of heroin, 37g of "Ice", 1,020g of cannabis and one Erimin-5 tablet, and $9,370 in cash.

CNB said that investigations into the drug activities of all three suspects are ongoing. The total amount of drugs seized was sufficient to sustain 1,770 heroin abusers, 460 "Ice" abusers and 420 cannabis abusers for a week.