Police say they have uncovered drugs worth around £7,500 from the postal system into the isles in recent months.
All of the recoveries were made with the aid of partners from the charity Dogs Against Drugs who monitor the postal system for suspicious packages as a matter of course.
In recent months a total of 13 packages containing drugs have been seized – leading to further searches of properties under warrant.
These have resulted in further recoveries of heroin, cannabis and cocaine.
Police say several people have been charged with drug offences, with other enquiries ongoing.
The recent searches came on Thursday after packages were intercepted. That resulted in searches of properties in Lerwick and Scalloway. Charges have been made.
Isles area commander Chief Inspector Lindsay Tulloch said: “We are very aware that the postal system is one means that people will attempt to use to bring drugs into our islands and we are committed to intercepting any suspicious packages before they reach their intended targets.
“The value of Dogs Against Drugs in this work cannot be overstated – they play a vital role in keeping the communities of Shetland safe.
“They are a local charity who now have four dogs fully trained and successfully operating in the islands thanks to the support of the local community.
“Drugs have no place on Shetland and will not be tolerated – not by us as a police force, not by our partners and certainly not by the community.
“I hope these recoveries send a strong message to anyone attempting to bring drugs into Shetland that we are watching. With the support of Dogs Against Drugs we will intercept your package and you will face prosecution.”
Anyone with concerns about drugs in their community can pass this information on to Police Scotland by calling 101 or by calling Crimestoppers on 0800 555 111.