Two Scottish tourists have been charged in Sydney after a report of suspicious activity at an Airbnb in Artarmon allegedly led police to a major ketamine discovery.

The investigation is tied to a short-term rental on Hampden Road, where neighbours reportedly noticed unusual behaviour on June 26. Those concerns were passed on to police, setting off further inquiries.

Police are alleged to have later found 105kg of ketamine in the boot of a car. The two Scottish tourists were then arrested and charged in connection with the case.

The Sydney Airbnb tip-off has drawn attention because a neighbourhood report at a short-term stay quickly developed into a serious drug investigation. The allegations against the pair have now moved into the legal process.