Royal Customs and Excise Department officers seized 4,254.32 grammes of controlled drugs and detained two local women in a vehicle inspection at Sungai Tujoh Control Post.
The two women, aged 27 and 22, were detained on September 9 during a routine inspection.
Several packages declared as car spare parts and souvenirs were found to contain dried plants suspected to be controlled items.
The items were seized and handed to the Narcotics Control Bureau for examination and further action.
Further examination confirmed the substances as controlled drugs with a total weight of 4,254.32 grammes.
In a separate incident at Kuala Lurah Control Post, Customs officers conducting a detailed inspection of a Brunei-registered vehicle found several undeclared black plastic packages.
The packages contained 360 cans of beer, 20 bottles of liquor and 200 packets of cigarettes of various brands.
A 37-year-old man and a 26-year-old woman, both local, were detained along with the vehicle.
The case has been handed to The Royal Customs and Excise Department Enforcement Division for investigation and further action.
The Royal Customs and Excise Department said it would continue inspections at all control posts to ensure compliance with the law and prevent the entry of prohibited or controlled goods.
Members of the public may report suspected smuggling activities or customs offences to The Royal Customs and Excise Department hotline at 8714422 or 8721422, or contact the nearest Customs office.