The sole occupant, a 29-year-old man from Te Anau, admitted he had just purchased the cannabis in Gore.
Te Anau staff continued inquiries at the man's home in Te Anau, where they seized cannabis, over $2000 in cash and drug-dealing equipment.
Sergeant in charge of Te Anau Police, Tod Hollebon, was pleased with the outcome.
"This has resulted in police taking a substantial amount of cannabis off the street, and uncovering a significant growing operation," he said.
Further investigation was carried out and revealed a 45-year-old man from Gore was allegedly responsible for the sale of the drugs.
A search of a Gore property was undertaken by staff and approximately 3kg of cannabis, several plants, and $10,000 cash were seized from that address, police said.
"I am proud of our local police working together across the borders in Riversdale, Mataura, Gore and Invercargill, which has resulted in two arrests so far," Hollebon said.
Both men were arrested. The 29-year-old will appear in the Invercargill District Court on drugs charges and the 45-year-old man will appear in the Gore District Court on similar charges.
Inquiries are continuing, and further charges could be laid, police said.