Police in Lerwick are appealing for information after a man was arrested on Saturday morning and suspected cannabis was seized.
Officers stopped a vehicle as it disembarked from the NorthLink ferry following its arrival at Holmsgarth.
It was searched and what is believed to be cannabis with a street value in excess of £16,000 was seized. A 41-year-old man remains in police custody and a report has been sent to the procurator fiscal at Lerwick.
Police are keen to speak to anyone who has any information and urged them to contact Police on 101 or via Crimestoppers.