About 2kg of heroin worth $220,000 was seized and seven suspected drug offenders were arrested on Tuesday.

Central Narcotics Bureau (CNB) officers were deployed in the morning to investigate a suspected drug courier. The Malaysian, 35, had left after placing a plastic bag at the rubbish chute of a block in Yishun.

When a 48-year-old Singaporean man arrived in a car to retrieve the plastic bag, CNB officers swooped in. Nearly 235g of heroin was found inside the plastic bag. A digital weighing scale and drug-taking apparatus were also found in the suspect's car.

In the meantime, a second team of CNB officers followed the Malaysian suspect and arrested him the same day at Hougang. About 1.8kg of heroin worth $193,000 was found on his Malaysia-registered motorcycle.

CNB officers rounded up five other men, aged between 30 and 54 years old, in Yishun on the same day. Small amounts of heroin, $4,150, and three cars were also seized.

Investigations are ongoing. If convicted, the suspected drug courier may face the death penalty.